This wasn’t Canadians! Stop telling lies! It was clearly The Joker. Look, he’s even painted the bat-symbol right there! He’s trying to taunt Batman!

Wouldn’t that mean it’s Batman?

When has Batman ever left his own symbol? It’s used by others to summon him.

to summon him

is he like a vampire or something?

I mean you only see him at night and he dresses like a bat… He also lives in a mansion, has a cave, and stays up all night.