For some reason, this Pokémon resembles a Poké Ball. They release poison spores to repel those who try to catch them
– Pokemon White Pokedex
Foongus looks like a Pokeball from the top. In fact, in the game, there are things that look Pokeball items, but when you go to put it up, it ends up being a Foongus, and you have to battle it. It’s a good disguise I suppose.
Despite there being so many Grass/Poison types in Gen I, Foongus and its evolution Amoonguss are the only Grass/Poison Pokemon introduced in Gen V.
Stat-wise, it has HP as the highest stat, has pretty even attacking and defending stats, and pretty low Speed.