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Poochy-Pups are younger versions of the character Poochy in Poochy & Yoshi's Woolly World. They follow Yoshi around the stage in Mellow Mode and help the player find secrets. When a secret is nearby, one will rush to it and start barking and jumping, waiting for the player to either find the secret or walk away (in which case the Poochy-Pup will return to Yoshi). Poochy-Pups can also be thrown like Yarn Balls; after being thrown, they will come back to Yoshi. Up to three Poochy-Pups will follow Yoshi at once.
Their behavior may be a reference to the behavior of the smaller Poochy from Yoshi's Story.