Poochy's History
Poochy debuts in Super Mario World 2: Yoshi's Island and reappears in the remake, Yoshi's Island: Super Mario Advance 3 (receiving no changes besides a graphical update). He can run on hazardous forms of terrain and charge through any enemies in his path. Poochy is ridden by jumping on his head and looking in the intended direction. He attempts to follow his rider after they dismount and waits under them if he cannot jump to their location, though he does not enter Warp Pipes and doors. He can also swim through lava and poison while carrying Yoshi. If Poochy reaches a wall, he crosses through a gap if one is present (which usually only fits him and not Yoshi), and otherwise tries to jump over it, even when he cannot make it across. While he is jumping, Yoshi can jump off his head. He can be distracted by throwing an egg at his head, which he plays with and does not pay attention to anything else.
Poochy only appears in three levels: 1-Extra, Poochy Ain't Stupid; 2-1, Visit Koopa And Para-Koopa; and 3-2, Jungle Rhythm...
Poochy returns once again in Yoshi's New Island, regaining his ability to walk on hazardous obstacles from Super Mario World 2: Yoshi's Island. He also behaves and is able to be controlled the same way, though he is now able to smash through certain types of blocks and grab items (such as keys) that the Yoshi can then take. He makes only two appearances in the game: first in 3-5, Don't Fear the Spear, which lets him demonstrate his new abilities, and then in 4-S, See Poochy Run!, where he must be used to clear the stage while avoiding maces and spikes.
Poochy appears in Tetris Attack alongside a Grinder as one of Yoshi's opponents, taking the place of the nature fairy Thiana from Panel de Pon. He was originally Yoshi's friend, but went against him due to a brainwashing spell cast by Bowser and Kamek. Once Yoshi defeats him (which involves playing the game's panel-based puzzles against him), he and Grinder are broken from the spell and joins Yoshi as he fights against Bowser. He is then unlocked as a playable character that can fight against the other brainwashed characters. There is no difference in gameplay, as the only changes are the appearance of the player's side and the sounds that play as panels are matched (cheerful barks as opposed to Yoshi's voice).
Poochy also appears in several levels of Yoshi's Story, helping the Baby Yoshis along the way. Although the Baby Yoshis are not able to ride on top of him, Poochy is able to find hidden fruits and hearts. In most levels, Poochy appears in a single spot, barking to show the location of a secret. However, in level 1-1, Treasure Hunt, he plays a much larger role. In that level, Poochy starts out chained to a post that can only be removed by ground-pounding it, which breaks the chain and frees Poochy. After being released, Poochy runs through the level and sniffs out hidden items. When Poochy discovers something, he stands by the spot and barks, and the item can then be revealed by ground-pounding. After the item is revealed, Poochy moves on to sniff out other hidden items.
Poochy returns in Yoshi's Woolly World, appearing in Spiky Stroll, Knot-Wing the Koopa's Aqua Fort, and Wonderful World of Wool. He has similar behaviors to those in his previous installments, though he has gained a few new abilities. Two Yoshis are able to ride him now, and they sit on his back rather than stand. In addition, he can now grab Smiley Flowers, Wonder Wools, and Keys in his mouth and bring them to Yoshi. As part of the game's wool motif, Poochy has a knitted appearance. If Yoshi tries to eat him, he will whimper, and if Yoshi ground pounds him, he will make a squeaking noise. He will bounce onto the course when a Yarn Poochy amiibo is used, but he will leave if he gets crushed or the Yarn Poochy amiibo is used again. He will respawn after he gets defeated or falls down a pit.
A purchasable Power Badge makes Poochy available at any course, but because his usefulness is very situational at most courses, it only costs 500 beads to use the badge, making it the cheapest one in the game. However, even when the badge is equipped, Poochy does not appear during boss battles.
Poochy & Yoshi's Woolly World, a Nintendo 3DS port of Yoshi's Woolly World, gives Poochy a more prominent role with a few additions. The Poochy Pups make their debut in Mellow Mode. They follow Yarn Yoshi around, assist the player in discovering secrets, and can be used as ammo instead of Eggs.
In addition, Poochy stars in a new mode, Poochy Dash. These are special levels that feature Poochy running endlessly to collect beads, similar to Super Mario Run. He will lose points if he bumps into something or falls down a Pit.
A Poochy amiibo was included alongside the game. Using the amiibo allows the player to unlock new designs for Poochy in the Poochy Hut. These designs can be unlocked by completing special missions in Poochy Dash, and can be used either in Poochy Dash mode or in the main levels.
Poochy and the Poochy Pups reappear in Yoshi's Crafted World. Poochy appears in the levels Poochy's Tape Trail, Poochy's Sweet Run, and Poochy's Magma Run. Like in the previous games, he helps Yoshi traverse dangerous terrain, as well as being able to grab Smiley Flowers as he could in Yoshi's Woolly World. In this game, Poochy is also capable of defeating some enemies Yoshi cannot. Whenever Yoshi stands still, Poochy may perform some playful animations.
The Poochy Pups reappear in the Flip Side versions of levels. Three are hidden in each level, and are worth one Smiley Flower each when brought to the goal. Although they can no longer sniff secrets for the player, as the Flip Side levels have no hidden collectibles aside from the Poochy Pups, they can still be used in place of eggs.
In addition, whenever Yoshi beats a Flip Side level with all three Poochy Pups in tow within the allotted time, Poochy appears to give the player a Smiley Flower.
The above text is from the Super Mario Wiki and is available under a Creative Commons license. Attribution must be provided through a list of authors or a link back to the original article. Source: https://www.mariowiki.com/Poochy