Spikeweed

destroys rolling objects and can hurt any zombie that step on it.

PvZ The Fall of The World
Almanac: Zombies? Hah! The only thing I'm afraid of is a giant... AHHH A WHEEL!!!

Plants Vs. Zombies: The Next Levels
Spikeweed's price has been reduced to 75.

Almanac: is in stealth, no zombie can see him. When they walk over him carelessly, Spikeweed takes them out. If only zombies would watch their step.