Oh, right, the stage.
Half the stage is some suspended leaves and vines to stand on and where most of the activity happens. The other half is a diagonal piece of earth that you never want to stand on because it's a walk off and drags you to your death in the rain.
It isn't legal to competitives.
If you stand on the Bulborb, it will sometimes eat you even though you're not even in its mouth. And it's far too fast to avoid. At least Sakurai fixed this when the stage returned in the 3DS ver- oh wait, he didn't! IT'S STILL THERE!