Bogs

If a square is part of a shallow bog, it has deep mud or standing water of about 1 foot in depth. It counts as difficult terrain, and the DCs of Acrobatics checks attempted in such a square increase by 2.

A square that is part of a deep bog has roughly 4 feet of standing water. It counts as difficult terrain, and Medium or larger creatures must spend 4 squares of movement to move into a square with a deep bog, or characters can swim if they wish. Small or smaller creatures must swim to move through a deep bog. Tumbling is impossible in a deep bog.

The water in a deep bog provides cover for Medium or larger creatures. Smaller creatures gain improved cover. Medium or larger creatures can crouch as a move action to gain this improved cover. A creature with this improved cover takes a –10 penalty to attacks against creatures that aren’t underwater.

Deep bog squares are usually clustered together and surrounded by an irregular ring of shallow bog squares.