Is the difficulty design of “Adventure in the Rain 2” a good design?


“Adventure in the Rain 2″[2]It is a third-person action shooting game with rouge elements. It is the sequel to the classic multiplayer roguelike platform action game “Adventure in the Rain”. The game easily inherits many design ideas from the rules, props, skills, and gameplay of its previous series, such as permanent death, items that can be linearly superimposed, and random levels that can be played repeatedly. This also reflects from the side of “Adventure in the Rain”. 》The design is very complete, stable and full of vitality, and the new perspective and the use of 3D models make the levels more in-depth and expressive.

The most unique and important mechanism of the game-the design of increasing difficulty over time[3]Has also been completely inherited. Although the title of the game may seem difficult to associate with these mechanics at first glance, there may also be an insight: in the expectations of the developers Duncan Drummond and Paul Morse, the description of “adventure in the rain” will evoke a feeling. It is related to opportunity. As a metaphor, it summarizes the risk and possibility of failure or adverse events that the small protagonist will face in a huge random world, and doubts will always accompany the player.

In addition, the game also deliberately combines a large number of rain-related images. For example, the three difficulty levels are named “drizzle”, “heavy rain” and “monsoon”, such as the name of the planet where the story takes place-Qiongni V( Petrichor V). Outside of the game, Petrichor is translated as tidal oil, which refers to the earthy smell produced by the first rain after the dry period. Its English word comes from the Greek word π?τρα (petra, rock), or π?τρο? (petros, stone) stone), and ?χ?ρ (īchōr, refers to the blood flowing in the body of the god in Greek mythology).This term was written by two researchers from the Commonwealth Scientific and Industrial Research Organization in Australia: mineralogist Isabel Joy Bear and RG Thomas (Richard G. Thomas) in 1964 First presented in “Nature” magazine[4]。

In “Adventure in the Rain 2”, it is the official name of the planet “The Planet”. In fact, the name was only used among players at first, and it was taken from a song of the same name in the original soundtrack of the game “Adventure in the Rain”. Although the official abbreviated it as “The Planet” during work and interviews, we can find evidence that it was used as an official name in the subtitle of the “Commencement” level.

In fact, this symbolic technique runs through the game. In the limited narrative of the game, the massively adopted second and third-person parallel fragmented texts pretending to be rational are quite polyphonic novels. In this context, the player will play the role of the crew of the UES spacecraft “Shunfeng”, a logistics company responsible for transporting goods to all parts of the universe, trying to find any survivors in the UES “light of touch” path in the previous game. In theory, the crew will In each round of randomly selected increasingly harsh environments, look for scattered teleporters for an endless loop. On the way, you need to fight against randomly born aggressive wild species to survive, and unlock more than 110 items Combine and use it until you defeat the ultimate leader on the moon-Mithrix-King of Nothing.

After reading the official description of “Adventure in the Rain 2”, the author believes that the game shows three unique goals: repeatability, tension and instant. First of all, in each round of the game, a random combination of monsters and props will be randomly generated to maintain high replayability and fresh challenges. At the same time, the difficulty of the game is equal to the time, which makes the game full of tension.Therefore, the designer hopes that the player will pay attention to each moment of the game process instead of the result, and do not have to worry about complex and non-intuitive game methods. In order to capture these moments, the designer recommends that players use theorycraft and loopholes in the game. exploit)[5]The former will also be the research method and means of this article.

So the player who is more intelligent may realize the hints and eternal puzzles hidden in the game: resource management and careful planning. This is closely related to the difficulty design of the game, and the management of time is also the long-term experience of human production and life.

The difficulty design is mainly divided into two parts in the game: Initial Difficulty and Scaling Difficulty. The former will allow players to actively choose before a process begins, and the three difficulty levels are named “Drizzle”, “Heavy Rain” and “Monsoon”. “Heavy rain” was conceived by Duncan Drummond and Paul Morse as the most suitable for most people’s normal rain conditions. Under this inherent difficulty, enemies swarmed. And “drizzle” and “monsoon” increase and decrease around it: for example, in “drizzle”, the game will give novices and adventurers who desire a more relaxing and enjoyable experience more long preparation opportunities at the beginning:

  • Time will be 50% of the normal speed for difficulty climbing
  • Players will have 70% higher armor value
  • Increases player’s health recovery speed by 50%
  • In addition, the player’s damage reduction increased by 38%

And every step on Mercury under “Monsoon” difficulty will bring pain and fear to the player.

  • Difficulty adjustment increased by 50%
  • Under this condition, the player’s health regeneration speed is reduced by 40%

The design of the initial difficulty is no different from other games with a static and slightly lazy optional difficulty system that is used to solve the difficulty problem, but the name gives it more drama and expressive tension. In contrast, Scaling Difficulty is so special. The experience it gives players is so subtle that it makes the entire series unique among many Roguelike games. Both the producer and the player have paid more attention to it: this design will Leading out the core challenges of the game, and echoing each other with the randomly superimposed equipment system, together to test the player’s mastery of operational abilities and skills and short-term decision-making in combination with the current environment. Under this mechanism, almost every frame will allow the player’s old abilities and choices to be fully tested, and once again acquire new abilities to face more difficult challenges.

The design with increasing difficulty over time is one of the consistent core mechanics of the “Adventure in the Rain” series. As a design that is constantly adjusted for difficulty, Scaling Difficulty is based on the initial difficulty selected by the player, and the subsequent difficulty development is directly equal to time. In the course of the game, the difficulty is steadily advancing and increasing, and the strength and number of enemies will continue to increase, making pressure and tension exist in each journey, leading to a chaotic ending and making it difficult to survive.

This design is visible. In addition to the increasingly stringent level conditions that can be perceived, the difficulty will be more intuitively indicated by the scale bar in the upper right corner of the screen-including the selected initial difficulty, timer and difficulty adjustment status.

As time progresses, it will pass through multiple sub-difficulty nodes in sequence:

  • Easy
  • Normal
  • Hard
  • Very Hard
  • Insane (crazy)
  • Impossible
  • I SEE YOU (I saw you)
  • I’M COMING FOR YOU (I’m looking for you)
  • HAHAHAHA……

This means that in the “torrential rain”, every five minutes, the difficulty will rise to the next bar with a faint bell ringing, and the enemy will also upgrade. This result is precisely controlled by the mathematical system, and the influence of time on the difficulty of the game is concentrated in a global variable called the difficulty coefficient (coeff). The coefficient is constantly recalculated, and its calculation formula is as follows:

playerFactor = 1 + 0.3 * (playerCount – 1)
timeFactor = 0.046 * difficultyValue * playerCount0.2stage
Factor = 1.15stagesCompleted
coeff = (playerFactor + timeInMinutes * timeFactor) * stageFactor

In this set of formulas, the variable playerCount is equal to the number of players in the game, including players who are unfortunately disconnected in the multiplayer mode; difficultyValue is different in different difficulty modes, and is equal to 1 in “Drizzle”. “Heavy Rain” is equal to 2 and in “Monsoon” it is 3; stagesCompleted is the number of completed levels, these levels also include other hidden areas except the space-time gap market, the number is the same as the number displayed at settlement; timeInMinutes is a round The number of minutes added is calculated every second from the start of the game. Based on this, the author tried to draw a diagram of the change of the difficulty coefficient in the single-person “drizzle” mode:

The change of difficulty coefficient coeff in the course of the game-single player-drizzle mode[6]

It can be seen that at the beginning of the game, the coeff will start from the middle of 1-1.9 according to the number of players. Then, as time increases, the difficulty will increase linearly, and at the same time, it will increase at a different rate depending on the initial difficulty and the number of players (the higher the initial difficulty, the more players there are, the faster the growth rate will of course). Each time a player enters a new level, the coefficient will increase by 15% of its current value, which will cause a leap on the difficulty scale. In a higher difficulty, such as monsoon, the multiplication coefficient becomes larger, and the further the player runs (run), these lines will become steeper and harsher, and become complicated and frantic rain falling on the player’s shoulders.

You see, this is the benefit of numbers. Its existence makes the increase in difficulty more intuitive and well-founded. It is also easier for us to evaluate the current and future situations, although the difficulty coefficient coeff cannot be used directly as a performance of difficulty. . So how is the difficulty reflected in the game? Every second, the system will calculate the enemy’s level:

enemyLevel = 1 + (coeff-playerFactor)/0.33

When reaching the next level, the monster’s HP and damage output will have a fixed increase. According to this formula, the monster’s HP and damage output will increase stepwise, and the growth curve will be more smooth in the later stage. The image still applies. The refresh rate of monsters is also an important manifestation of difficulty, but because it is very important, the game arranges a more advanced event system (Director) for independent management, responsible for generating various enemies matching the difficulty.

The system accumulates many credits over time, and these credits increase linearly as the coeff increases. The system will regularly generate up to four groups of monsters randomly according to the corresponding generation list of the environment and spend points (the maximum number of enemies that appear on a map at the same time is 45). Ordinary monsters like Lemurians cost less points, while bosses like Magma Worms cost more. The “price” of elite monsters is 6 times that of ordinary monsters. This means that when the difficulty coefficient coeff is low, the system can only produce a single, weak enemy. But as time increases, the budget of the system will also increase, weak enemies become less and less common, and more and more powerful monsters are produced.

Whenever a new monster is generated, the reward the player gets for defeating it will be directly multiplied by the current monster value coefficient:

enemyXPReward = coeff * monsterValue *rewardMultiplier
enemyGoldReward = 2 * coeff * monsterValue *rewardMultiplier

Most monsters appear in the game with a variety of power levels. MonsterValue is equal to the basic version value of the monster multiplied by the elite level it is in. The higher the monster, the higher the attributes and unique abilities, appearance and There are also differences in the performance of blood bars. Eliminating them will naturally have higher rewards. The rewardMultiplier is related to different events that occurred, including portals, battle shrines, and other scene systems, which are 0.02, 0.2, and 0.0666667 respectively.

Elite level[7]

But at the same time, the cost for players to obtain items is also increasing:

moneyCost = baseCost * coeff1.25

This means that benefits and costs always increase together, but there is a question of who is fast and who is slow. Cost is the final test that difficulty brings to players. When a new environment is reached, the cost of opening boxes, shrines, turrets, etc. will be calculated relative to the difficulty. At the same time, players need to determine the opportunity cost and time cost of opening based on the current environment. Since the reward multiplier is also managed by Directors, the monsters do not appear in obvious waves in the game. Therefore, when a monster is generated, its reward will be refreshed. This way, in the later stage, the reward will be obtained. It is also huge, and it is easy to have tens of thousands of resources at the beginning of the game. Here players need to decide whether to stop and pick up these items-this is how I ended my 367-minute journey easily. This kind of design is too straightforward to look at on its own, without its own feedback and restrictions, but after all, the unused gold coins will be converted into experience when they are transmitted, although the change is not obvious compared with the props.

Combining these formulas, the process players go through is often like this:

When the player crash-landed on Mercury, the world was very calm. The survivors of the UES “Shunfeng” traveled in a completely unfamiliar area. The gentle BGM came from leisurely and seemed very relaxed. The player encountered very little resistance and the enemy would always Level 1 starts. Sometimes the player will impatiently want to find more opponents. At this time, it is more useful to find the battle shrine. It will summon a certain number of monsters for the player to kill additional monsters to get more gold coins. The player needs to find the teleportation device, solve the powerful enemy that appears in the portal event, and enter the next environment.

Soon, the game becomes more and more demanding as time, coeff increases and levels advance. The faster the enemy coefficient increases, the more effects will become more obvious. Monsters that continue to refresh and spawn faster and faster will inevitably accumulate. Monster levels are getting higher and higher, making it more and more difficult for players to deal with. After a while, more powerful enemies will start to spawn outside of the portal event, including mini-boss (such as ghosts) and portal bosses (such as golem). Higher difficulty also increased the frequency of elite monsters, and even elite-level mini-Boss and portal bosses began to appear. When the player is in front of the obelisk and in the market between time and space, the player will get a moment of relief and then rejoin the challenge.

Because time will not wait, the difficulty when it comes to HAHAHAHA is endless, although no changes can be seen on the indicator bar, the player walks on the edge of death and the flame rain every second. In addition to the orderly increase in difficulty over time, every time you enter the next environment, the difficulty will jump forward, which will cause the difficulty to increase sharply and the indicator bar will increase faster. This means that as time continues to elapse, more level loops are completed, and the more players in the later stages feel isolated and helpless in this huge unknown world, their sense of security is stripped, and the game becomes more and more difficult. The protagonists are always in Will be swallowed by raging beasts and will be killed by the planet. When the player chooses to land on the moon, the drizzle really falls on the surface, and the player takes a breath in the continuous one-way passage. When the BGM suddenly climaxes, the long-repressed emotions along the way are in flames with the final boss of the King of Inaction Then he was released and ushered in the chaotic end of the adventure in the rain.

We can discover from this narrative how the game designer uses difficulty to mobilize the player’s emotions. The player’s experience of difficulty runs through the game, and this is a complete journey. Designers build and expand games closely around this experience design. And when we have a specific concept of the difficulty design, and can predict the situation the player is facing at any time, we can look back at our question. Is the difficulty design of “Adventure in the Rain 2” a good design?

We have summarized the two difficulty designs of “Adventure in the Rain 2” earlier. For Initial Difficulty, many games with a little consideration will provide players with different difficulty choices at the beginning. This design is quite satisfactory, but it may not be a good design. It gives players part of the power to choose difficulty. Just imagine When the player has just joined the UES route, he has to face the choice of difficult circumstances, and he is required to choose a suitable difficulty mode. Although “Risk in the Rain 2” gives specific data, these values ​​are based on a series of events in “Heavy Rain” Basically, the player does not know the specific situation in the “torrential rain”, nor can he perceive the difference between the simple and the difficult, and is not clear about the risks and rewards of each choice.

In short, letting the player determine the difficulty level at the beginning of the game is a luck-related idea. It is based on the player’s general feeling of ambiguity, which may also come from experience in daily life and other games in the past. This will make players misjudge and force self-identification. In the absence of sufficient information, based on a brief introduction the player has to make an important commitment concerning the entire journey. Once a choice is made, the player will endure the difficulty that may be too easy or too difficult throughout the next game.

At the same time, this idea usually ignores that the player’s ability will float, and cannot consider the player’s later learning ability. After all, the design of difficulty is always closely related to balance. When the player’s ability to be trained exceeds the imagination, the game will start to become Uninteresting, these will also cause the audience of the game to become smaller, and the duration of the game will also decrease. In some games, another problem caused by clear difficulty settings may be that players are no longer paying attention to the work itself, and at which difficulty does the game present its true original appearance, but only the adjustment of the data Raise or lower standards. Some players will be very concerned about this. For some developers, this design has become a universal shortcut to improve gameplay. This tradition may have continued since the arcade era, but it is actually just an additional supplement and repair. Except for special experience purposes, the communication between the developer and the player through this method is more useless consumption, rather than the true expression of both parties’ understanding of the game.

For Scaling Difficulty, many games will be more difficult in the later stage, but they are generally arranged on scripts and key nodes. Generally, the longer the player invests and the deeper the progress, the more difficult they face. But the “Rain in the Rain” series with roguelike elements makes players more familiar, the more nervous they are. “Rain in the Rain” directly takes out the difficulty and allows time to keep advancing. This pressure drives the rhythm of the entire game and actively limits it. The negative behavior of players repeatedly spawning monsters and so on-simply swiping experience will not allow you to face the more difficult levels later, to ensure that the game has been going on. But this design alone looks very straightforward, mechanical and lifeless, like static dynamic adjustment-because it is not a static difficulty choice, but it is not a dynamic difficulty adjustment (DDA, Dynamic Difficulty Adjustment) , It is between the two, and the biggest difference from them is that the player has no active choice and control over the difficulty. The creators naturally have their purpose in doing this. Duncan Drummond and Paul Morse originally made “Adventure in the Rain” into a tower defense game. Players must protect damaged spaceships against the intrusion of monsters. The difficulty is not with time but with As the distance between him and the spaceship becomes farther, it increases gradually. But this also resulted in the players not having the motivation to leave the spacecraft. So in order to drive players to keep moving and exploring, they overturned the entire base defense design and came up with a system solution where time equals difficulty. This makes the purpose of the game clear and the rhythm tight. But when the player is pushed forward, it may be easy to face a situation like being raped and helpless, starting from the beginning.

This is the same as the other important system in the game-Items (Items). Since most of the item stacking is linear, each additional one will simply add that value, and the game does not limit the type and number of items the player can pick up. , The gain of character upgrade is obviously not as good as the effect of props superimposed, which makes props the key to enhancing characters. The linear superposition mechanism also makes the props easier to understand, allowing the player to immediately recognize their current strength. Except for those lunar items with weird and fuzzy entries, the player does not need to deliberately consider too many matching solutions. But this also seems to make the designed “Synergies” between the props a bit wasteful, and the player’s short-term decisions are further weakened. Before using the artifact, the number of equipment that can be obtained in each level is limited, which makes the growth of the characters generally show a trend of rising polylines-the design of polyline growth is generally considered to be weird and will cause players to fall into the experience fault. Players’ increasingly stronger design also makes the game form a positive feedback loop in this regard, killing monsters to gain experience points and assets to buy equipment to become stronger, so that players can kill monsters faster, players will continue to Be strong and addictive. The positive feedback loop can also help to push the game to the end and avoid a long battle, but as a roguelike game with no end, the positive feedback loop obviously can’t help much here. It is the king of the ultimate boss. Before the launch, players who have been playing for dozens of hours will become addicted and become numb and confused. They will no longer experience any changes in the game and have to quit the game. After exiting, in addition to the record of a single game, the player will not receive any rewards for his performance. This feeling of being stripped is very serious.

Obviously, when the difficulty continues to rise, the game needs to help players increase their ability to face the more difficult levels behind; and in the process of infinite improvement of the player, corresponding challenges are required to limit the player, which is a bit like traditional Japanese RPG , Through two sets of positive feedback to coordinate to eliminate the Matthew effect, or like the “rubber band effect” and blue tortoise shell in Mario Kart. Now there are two lines in front of us. One keeps giving problems and the other makes the player stronger. Therefore, it is easy to perceive that the experience brought when the two meet will make everything different. This is balance. .

This balance is not only about numerical values, but also player psychology. As time flows more frequently, the increase in difficulty makes the challenge curve smoother, and the acquisition of equipment will make the steadily increasing character growth suddenly rise to another level. The asymmetric growth lines drawn by them control the game system, and the difference in between is It’s the player’s heartbeat gap.The player will temporarily be stronger than the monster, and soon the monster will surpass the player again, and the strong and the weak will change rhythmically.[8]. Before each deeper understanding of the game mechanics, sometimes the difficulty suddenly drops and the player feels that they are strong, and sometimes the difficulty suddenly rises. As an inconspicuous punishment, the player realizes that they have deviated from the game’s expectations, as a signal. Let the player perceive that something bad has happened. So players began to face choices. Either directly find the teleporter and activate it to pass the level quickly, or kill the enemy as much as possible, clear the entire map, and open all the treasure chests. This makes the player’s sense of profitability not so strong, on the contrary, they still feel that the boss is terrible, which makes the player more cautious. There are advantages and disadvantages to the choice between growth opportunities and the control of increasing difficulty. These strategies themselves are what an elegant difficulty design requires: it revolves around the game’s mechanism and closely follows the theme, and requires players to do it through the various elements provided in a limited time. Interesting choices and complex manipulations.

At the same time, the combination of difficulty design also shows the designer’s expectations-to make the game appear deeper or to make the player more proficient, allowing players to play at multiple levels. In “Adventure in the Rain”, players can first serve as learners, and novice players can use the “commander” to output randomly, explore and understand a small part of the game system and rules in the drizzle, experience a gentle increase in difficulty, and ensure that They will be very happy in terms of numerical value, ability and experience. Although the score may be bad and the distance they ran before death is not far, it is still a good accumulated journey. In the second layer, the learner becomes a player. At this time, the player adapts to the change in difficulty, realizes the depth of the game, uses the basic rules to make interesting decisions, and allows them to express themselves. This is related to adding new mechanisms and unlocking new objects. It has nothing to do, but can do the right thing at the right time. Players will think about every step to be done, and no longer regard difficulty and equipment as independent things, so that the mechanism can be more effective. On the third level, players will perceive that there is more depth in the game, and use techniques and strategies that only they have discovered. These techniques are just an evolutionary version of your previous learning mechanism, such as being able to successfully use the synergy effect of props to greatly improve attributes, or It is an extension of the operation and more flexible shooting and positioning-players need knowledge, timing, agility and skills to use them.

Separating the rewards from the game progress in the “Monsoon” difficulty is also a good design method. In this difficulty, there will be higher challenges, and the high-tech players will be given more rewards, test the player’s ability and skills, and create encouragement for the players Pursue that “elegant” model and opportunity. For example, challenging the “Monsoon” will not give players gold coins or extra lives. On the contrary, players will open high-difficulty rewarding Deicide challenges and mastery challenges, reach new areas to explore, slide on the soles of giant monsters, and cooperate with higher difficulty. Under the brand new paper doll system, everything looks great. This is a great reward for gamers who have proven themselves. In terms of mechanism, we have tried our best to avoid the similarity in the process so that players who pass the level with the difficulty of “drizzle” and “heavy rain” do not want to challenge the “monsoon” that may lead to useless effort and deep waste. These challenges will inspire players to explore the second and third levels of depth and use their skills harder.

However, crazy animations, absurd actions and superimposed pure and dramatic exaggerated effects increase the aesthetics and watchability of the game, which means that novice players can also enjoy the game. And these additional difficulty and depth means that people who spend time learning and mastering the game and those who are eager to challenge will be rewarded. The designer recommends that players use theorycraft and exploits for the game. This is a progressive difficulty presented as a whole. It allows the aforementioned designs to not be wasted at all and ensures that any provided The props have a certain practicality and balance.

This is the secret of many enduring games, most of which are based on Nintendo’s design strategies for many years: these games are friendly to novices and provide all players with an easy-to-handle basic experience, but they have a high hidden difficulty ceiling. Advanced players can also enjoy it for several years. It allows players of different types and motivations to control and express themselves, make interesting choices, flexibly use the main game mechanics to make more styled and effective actions, and the more you pay, the more you gain many. Difficulty design needs to give players a proper chance to prove their strength and a greater chance of obtaining satisfaction. Like the fireworks displayed by the player at the Mercury Carnival, even if the only lonely soot left after the burning, the starting point of this process is like wine, perfume, and the itch on our body. The short-term high return stimulation is always Continue to attract players.

In the end, this design allows the player’s expression to echo the designer’s purpose, which is Organic Difficulty.[9], “Adventure in the Rain 2” allows players to interact with the game through a specific way of self-expression to change its difficulty. These methods are the decisions and trade-offs we mentioned earlier. This method is used in an increasing number of games. It allows players to experience the designer’s design experience without destroying their own game experience, making you feel weak and helpless, just to enhance your pleasure.

Difficulty design and feedback loops are key design parts of many games. And the difficulty design of “Adventure in the Rain 2” is so unique that it stands out from many Roguelike games. Although few players will play this game against this design, most players will still be overwhelmed by the exaggerated performance and infinite overlap. Attracted by equipment, players who prefer difficulty will also play more hardcore games. But please don’t forget that difficulty design is the soul of this game. Its existence drives other systems and players. If you lose it, even the prop system will be eclipsed.

“Adventure in the Rain 2” is so well integrated with the game that it seems difficult for other games to learn from. This design can be so successful because it is a Roguelike game. “Randomly generated” means that players cannot directly choose a perfect strategy and must adapt to the game according to the circumstances. They build themselves around the props and relics they got early. In the ever-increasing difficulty, players will always think about it, and open a box to meet the most powerful equipment. This also makes the game more engaging and addictive. The two do not conflict. . When players have a sense of “synergy”, it is easy to form their own fixed strategies, which may attract you to explore and repeat them, but before long, the game becomes a bit boring. But the “permanent death” of “Dream in the Rain 2” requires players to start every round, either because of death, or because you want to try a new character or higher difficulty after winning, so the strategy will not ruin the balance.

But this does not mean that “Adventure in the Rain 2” is useless for other games, or that our discussion here is not meaningless. This design provides a new reference for the difficulty design. Although many Roguelike games have begun to use this difficulty method, such as the hunger mechanism, they are not as good as “Adventure in the Rain”, because all the designs are related to the difficulty. Matching, difficulty design becomes the game itself.

Most importantly, design needs to serve game expression. When a design makes players misunderstand, it is not a good design, so consider clearly whether the game requires the application of difficulty design. “Adventure in the Rain 2” respects players. It does not divide a player’s level and tries to please them or respond with contempt, but to cultivate and encourage the player’s interaction with the game. At the same time, it helps us restore the sensitivity to time that is gradually lost in life. Time is not gentle. We no longer live in time, but parallel to it.

It lets us know that as a living being, time coexists with us and dies with us without hesitation.


Source: Machine Core
Original: https://mp.weixin.qq.com/s/w_u7Aptt08aqucVQPoOznA

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