Same slugs that turn people into zombies and form to become a monster thing. I'm sure they got ideas from that movie for this game.
"You killed Captain Clown, YOU KILLED CAPTAIN CLOWN"-The Joker on Batman TAS
I saw Night of the Creeps years ago on VHS and since acquired it on DVD, and I played through RE0 when my friend let me borrow his Gamecube and copy of the game (I never actually owned one). Although I see the connection, there are a handful of slug-based horror movies out there, like Shivers, Slither and Slugs. There could be doubted that RE0 was influenced by NotC, but considering it's the best film of the ones I mentioned I'd give it the benefit of the doubt.
Then again, it could have been influenced by Splatterhouse.
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