Plaid Patrick is the alternate universe version of Patrick Star, who comes from a universe where Patrick is plaid. He may come from the same universe as Blue SpongeBob or Red SpongeBob.
He is extremely similar to the original Patrick Star, but his skin is a blue plaid pattern in the comic. On the cover, it is instead a red plaid pattern.
He is one the third alternate universe characters that SpongeBob summons into Bikini Bottom 2 after Sandy Evil-Cheeks. The other two are Green Patrick and Patrick Star.
He also appears at the end with a bag of chips.