FusionDex

These Pokémon live within ponds, their metal bodies so heavy that they are often stuck at the bottom of them. The metal of their bodies is rather transparent, to the point you can sometimes see their internal organs.

It is possible to see this Pokémon's spiral innards right through its thin skin. When Belwag gather in a swarm, they move in perfect unison as if they were but one Pokémon.