The plant in the original game that shoots homing spikes at zombies is Cattail.
Cattail is an aquatic upgrade plant that fires spikes which automatically seek zombies. Unlike most plants, it does not have to attack only the lane where it is planted: its projectiles can track targets across the lawn. That flexibility makes Cattail valuable when zombies appear in several lanes at once.
A common mix-up is Tangle Kelp, another water-associated plant. Tangle Kelp is a single-use plant that pulls one zombie underwater, whereas Cattail is a permanent attacker. Lily Pad is also not the answer; it is the support plant used to place non-aquatic plants in pool lanes and the prerequisite for obtaining Cattail.
In the original Plants vs. Zombies, Cattail is obtained as an upgrade through Crazy Dave’s shop after the pool sections become important. Its homing attacks can also deal with Balloon Zombies, giving it a role beyond ordinary lane defense. The plant’s design combines a cat’s face with a cattail’s spiky flower head, matching the game’s habit of turning visual jokes into mechanics.