Bumblers are bees in Grassy Greens from the game Mario Pinball Land. If Mario touches a Bumbler, it tries to chase Mario, with his sting facing the direction it goes. Mario mustn't touch a Bumbler forward in such position of this enemy, else Mario will get stung, making him out of control. Mario must hit its back instead, to defeat the bee. Bumblers will give up after a time if it can't sting Mario, and sets in its original position.
Bumblers will only appear in the second part of Grassy Greens, with the windmill where Petey Piranha awaits. Bumblers also only appear if Mario hits the beehive near the windmill, where three of them come out. When ignored after a long time, Bumblers will retreat back in their hives.
Mario has to defeat all three Bumblers if he wants to earn a Star.