Please remember that WiKirby contains spoilers, which you read at your own risk! See our general disclaimer for details.
CPU
The term CPU (short for 'Central Processing Unit') in the context of video games refers to elements (such as characters or enemies) whose behavior is controlled by processes programmed into the game itself. More specifically however, it is used to refer to secondary players who have been set to be controlled by the game itself, rather than any human player.
In the Kirby series, CPU players (also referred to as Computer Players) can be set in any multiplayer title to stand in for real human opponents, and they are programmed to simulate how said human opponents would play to a certain degree.
Overview[edit]
CPUs often come with difficulty settings as well which the player can set to make them more or less of a challenge. The change in difficulty usually alters how quickly the CPU can react to a given situation, and whether or not they will perform certain behaviors (an example being the CPU players in Kirby Battle Royale, who are programmed to actively pick up their downed opponents and toss them into hazards at higher levels).
In most games in the series, common enemies are controlled at least to some extent by CPU programming (the original Kirby's Dream Land is an exception; Masahiro Sakurai manually plotted the paths for every enemy in the game, making them completely deterministic[1]). However, these behaviors are usually quite simple, amounting to little more than holding still, jumping in place, attacking in fixed intervals, or pursuing Kirby. CPU players, on the other hand, are typically given much more advanced algorithms and conditions which will cause them to behave in more complex manners, in an attempt to simulate strategic human play. Given the imperfect (and simplistic) nature of this programming, however, CPU players often have trouble in certain situations, and can be locked in endless behavior loops which get them nowhere.
CPU by title[edit]
Kirby's Avalanche[edit]
Kirby's Avalanche inherits much of its CPU behavior from the game it is based upon, Super Puyo Puyo. Aside from the overall difficulty level that can be adjusted manually via the options, each CPU has its own characteristic behavior that affects how it plays. For example, Waddle Dee never turns any of his blobs, and rarely makes them drop faster, causing him to play rather slowly and languidly. In contrast, Meta Knight is especially skilled at making a comeback when most of his playing field is filled with boulders, causing him to play quickly and intelligently.
Some CPUs have particular behavior they will always stick by no matter what, even if it may be impractical to do so; these behaviors are referred to as "first-instinct chains". Whispy Woods, for example, will always start his round by building four rows of blobs at the bottom of his playing field, and will replenish the wall if any of the blobs within it are destroyed. Broom Hatter shows similar behavior, but instead builds two full columns of blobs on the left and right sides of her playing field.
Kirby Super Star / Kirby Super Star Ultra[edit]
The Helpers in Kirby Super Star and Kirby Super Star Ultra are controlled by the CPU when not controlled by a second player. These CPU Helpers have more sophisticated behavior when compared to common enemies or bosses, most of which operate on a pre-determined set of patterns. This allows the CPU Helper to follow Kirby and help him battle enemies. In some cases, they can also help solve certain puzzles, with a prime example being Burning Leo's tendency to light Fuses that are nearby. The CPU can pick up food items and Invincible Candy, and will move toward Kirby to share them via Feed Me, though this is just a side effect of the normal CPU tendency to get close to Kirby, and it will not prioritize this over attacking enemies.
Under normal circumstances, the CPU Helper will approach Kirby and stand close by when he is not moving. The CPU will not be prompted to follow Kirby until he gets a small distance away. When Kirby is in the air, the CPU will generally not follow him up there, preferring to just keep underneath him on the ground, unless the environment prompts it to. Once this happens, the CPU will use its Infinity Jump to continually keep close to Kirby when he is in the air. Certain terrain, particularly tight passages, may confuse the CPU, making it unable to properly follow Kirby (shown in image).
When an enemy is nearby, the CPU will attempt to navigate towards it and attack it, with the type of attack depending on whether the CPU or the enemy is in the air or on the ground, though this can often lead to the CPU crashing into the enemy and taking damage if the path is complicated or if the enemy is moving rapidly. The CPU may alternatively choose to guard, though it rarely holds its guard for long. The CPU's attack options are performed on a timer when choosing between multiple targets, with noticeable pauses between attacks or guards in these instances. In certain situations, the CPU may have difficulty deciding whether to follow Kirby or attack an enemy, so it will run back and forth between the two objectives fruitlessly until the situation changes. When enemy projectiles are approaching, the CPU will either attempt to guard or attack it as if it were an enemy. During boss and mid-boss fights, the CPU will engage the enemy from any position, rather than having to get up close first.
The CPU will not attempt to break blocks, activate switches, or use ladders. The CPU will also not attempt to avoid hazards such as Gordos or spike pits, which can lead to situations where it continually stands on or in the path of such hazards until it is defeated. When the CPU is out of health, it will no longer try to follow Kirby around (unless Kirby gets sufficiently far away) or attack enemies, instead holding in place until it pops out of existence. If prompted to move in this state, the CPU will run frantically around Kirby once it reaches him until it pops.
Kirby's Dream Land 3[edit]
In Kirby's Dream Land 3, Kirby can call on Gooey to help him, with the cost of some health. When not controlled by a second player, Gooey is controlled by the CPU. Like the Helpers in Kirby Super Star, Gooey will generally attempt to stay close to Kirby and attack nearby threats, possessing almost all of Kirby's moves. Unlike Helpers, however, Gooey's CPU is much more oriented around mimicking Kirby's actions when there are no other considerations on screen. For instance, if Kirby performs a basic action such as jumping, inhaling, crouching, or sliding, Gooey will usually mimic him after a brief moment, granted the opportunity to do so. This includes walking itself, since if Kirby only steps forward a small amount, Gooey will also only move forward that same distance instead of stopping at Kirby's position like the Helpers do.
Gooey's general attack strategy is to approach enemies and eat them with his tongue, and then spit them out as a Star Bullet at another enemy. Gooey will generally hold onto any enemy he has eaten until he spots another enemy to shoot at or Kirby prompts him to by attacking or crouching. Gooey will pursue enemies at greater distance than the Helpers do, but he may still end up colliding with enemies and taking damage if the environment confounds his efforts to run up and eat them. Notably, CPU Gooey will not attempt to swallow ability-granting enemies to gain an ability, despite having that capability when controlled by a player. As such, it does not appear to be possible to have CPU Gooey utilize copy abilities.
CPU Gooey will not attempt to pair up with an Animal Friend, despite having that capability when controlled by a player. When there is a food item nearby, Gooey will use his tongue to get it, and then will send half of it to Kirby as a projectile to heal him as well. Unlike the Helpers, CPU Gooey is capable of activating a Space Jump on his own initiative, and will do so if he cannot find a path to Kirby.
