When LEGO Batman makes his big screen return in the appropriately titled "LEGO Batman Movie," the Will Arnett-voiced Brick Knight will be joined by a host of classic heroes and villains from across the Bat-universe.

The film's final poster, which boasts the Internet meme-generated phrase "Always Be Yourself... Unless You Can Be Batman," offers a look at the movie's expansive cast, with Joker, Harley Quinn, Two-Face, Clayface, Killer Croc and more chasing after Bats, Batgirl and Robin. Joining them are some newly revealed characters, including Hugo Strange, Black Canary, the Wonder Twins and one of the meanest character from Frank Miller's classic "The Dark Knight Returns" -- the Mutant Leader.

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Debuting in the decidedly not kid-friendly classic '80s comic, the Mutants are a gang dedicated to terrorizing the Gotham City of the future. Their leader faces off with an aged Dark Knight in one of the story's most famous scenes which sees the geriatric hero take down the younger, stronger villain in hand-to-hand combat. As a result, the Mutant gang switches allegiances and becomed a Batman-themed force for good in the city.

Arriving Feb. 10, 2017, “The LEGO Batman Movie” is directed by Chris McKay from a script by Seth Grahame-Smith.