Cactus

shoots spikes at zombies and can also pop Balloon Zombie's balloon.

Plants Vs. Zombies: The Next Levels
Cactus is nowhere to be used in the game, and is instead replaced with Aspearagus. The only times it is seen is on a Litter Zombie's milk carton, in the end credits's second song and in the trailer shown on Newspaper Zombie's Newspaper.

Plants vs. Zombies: Around the World
Cactus is referred as a boy. He shoots spikes and can't be eaten by zombies.