Bob-Omb Battlefield: Mario's floating power
Select Mario and collect either Wario's or Luigi's cap to turn into that character. Then, lure an enemy to the red power-up box. Break the box while wearing Wario or Luigi's cap and a Power Flower will appear instead of the Feather. Then. get hit by an enemy to turn back into Mario and collect the flower. Mario will float instead of getting the Wing-Cap. This trick can also be done in other levels that will give Power Flowers to Wario or Luigi (but not to Mario), as long as you can get hit to lose the other character's cap and collect the Power Flower as Mario before it disappears.