Great guesses and replies, guys. Thanks, y'all.
The Rabbit is from Monty Python and the Holy Grail. It's the Rabbit of Caerbannog.
The Alien has met his match... the rabbit will pounce on the alien and then it's bye bye mr. Alien. Lol
Here is a little dilogue from the movie.
TIM: There he is!
ARTHUR: Where?
TIM: There!
ARTHUR: What, behind the rabbit?
TIM: It is the rabbit.
ARTHUR: You silly sod!
TIM: What?
ARTHUR: You got us all worked up!
TIM: Well, that's no ordinary rabbit!
ARTHUR: Ohh.
TIM: That's the most foul, cruel, and bad-tempered rodent you ever set eyes on!
ROBIN: You tit! I soiled my armor I was so scared!
TIM: Look, that rabbit's got a vicious streak a mile wide! It's a killer!
GALAHAD: Get stuffed!
TIM: He'll do you up a treat, mate.
GALAHAD: Oh, yeah?
ROBIN: You mangy Scots git!
TIM: I'm warning you!
ROBIN: What's he do, nibble your bum?
TIM: He's got huge, sharp-- eh-- he can leap about-- look at the bones!
ARTHUR: Go on, Bors. Chop his head off!
BORS: Right! Silly little bleeder. One rabbit stew comin' right up!
TIM: Look!
[squeak]
BORS: Aaaugh!
[dramatic chord]
[clunk]
ARTHUR: Jesus Christ!
TIM: I warned you!
ROBIN: I done it again!
TIM: I warned you, but did you listen to me? Oh, no, you knew it all, didn't you? Oh, it's just a harmless little bunny, isn't it? Well, it's always the same. I always tell them--