Moss is green coloured and appears in clumps which vary in size. Larger clumps of moss appear dark green towards the center, while smaller clumps and the outer edges of larger clumps appear light green.
Moss appears in all levels of Bomba, most of it which has to be destroyed. Bomba will die if any contact is made with the moss, or walls. Moss most of the time is seen filling up hallways, blocking the player's way. Moss can be destroyed by either using bombs or becoming fiery via the flame pickup.
Moss is sometimes placed so that it covers some parts of wall, but it can't cover obstables. Enemies cannot be harmed by moss, only Bomba can. When moss is blown up, some bits of moss will still be present. Moss will float up to the top of water, but only pieces of moss detached will float to the surface. Two types of moss creatures, creatures made of moss, appear in Bomba. One slithers in an irregular way while the other increases and decreases its size.
When moss is blown up, some pieces may stick to remaining pieces of moss on the wall.