Shamrock

Shamrock is a plant in Plants vs. Zombies Adventures. Its VIP version is 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, making itself act like the Scaredy-shroom. This makes it best to keep Shamrocks 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 (though they technically can still be killed by Gas Can Zombies' explosions).

Trivia

 * When it's hiding, its shell cannot be seen on the outside.
 * Shamrock and Shamrockstar can only be KO'd by a Gas Can Zombie explosion.