Shamrock

Shamrock was a plant in Plants vs. Zombies Adventures. Its VIP version is the Shamrockstar. It is a powerful offensive plant based on a four-leaf-clover, which is a mutated plant from the genus Clover (Trifolium). Shamrocks are the young sprigs of all the clovers in that genus.

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You could say Shamrock is lucky, if your definition of “luck” includes “hiding whenever there’s anything dangerous or herbivorous around.” Which is a kind of luck, you must admit.

Strategies
If zombies comes close to Shamrock, it will hide like the Scaredy-shroom. This makes it best to keep Shamrocks as far away from zombies as possible. Its also good to put it in a spot where only one path can get to it. Unlike Scaredy-shrooms, hiding Shamrocks are ignored by zombies, making Shamrocks practically invincible (although they technically can still be killed by Gas Can Zombies' explosions).

Trivia
Трилистник
 * When hiding, its shell cannot be seen on the outside.
 * This easily foreshadows the Aspearagus, because of the same sun cost, same range, and deals more damage.
 * Shamrock and Shamrockstar can only be knocked out by Gas Can Zombie's explosion.
 * Shamrock, Shamrockstar, and Magnifying Grass are the only plants that shoot rainbows.
 * When it is hiding, it somewhat resembles a rock.
 * This, Shamrockstar, Blover, Four-leaf Blover, and Fan Blover are the only plants that resemble clovers so far.
 * It shares traits with Scaredy-shroom, as they both hide when zombies come closer to them and launch projectiles towards zombies that are far away.