Evil Squidward is an evil clone of Squidward. His looks appeared in “Squid’s Day Off” in Spongebob while locking his front door in his house and then he was running neud to the Krusty Krab and caught Spongebob (until he were daydreaming about Spongebob annoying him and his bath). Evil Squidward often tried to kill the original Squidward but to no success because, like his original, he's nothing but a failure.
On the bright side, he was able to steal Squidward's ID and give him a massive amount of credit card debt which Squidward still has to pay off. Currently, Evil Squidward is enjoying a topical cruise on his private yacht which he bought with Squidward's money.