Seesaw Shroom (blue)
From the Super Mario Wiki, the Mario encyclopedia
Blue Seesaw Shrooms appear in New Super Luigi U and its remake. Like their normal counterparts, they tilt slightly from side to side when idle, but balance under the weight of players when they stand on it; however, they also feature low traction, causing players to slide across if they are not in their Penguin form. These Seesaw Shrooms also come in two sizes, with one size being slightly larger than the other. They only appear in the level Cooligan Shrooms, where they are extremely common.