A splitting maul also known as a block buster, block splitter or "Godevil", is a heavy, long-handled axe used for splitting a piece of wood along its grain. One side of its head is like a sledgehammer, and the other side is like an axe.

The maul is most commonly struck onto a flush-cut section of log, usually standing on end atop a splitting stump or other suitable base. Most cut sections can be split in a single downward chop of the maul, splitting the wood apart along its grain. Mauls regularly become stuck in the log for several reasons, such as the wood not being struck with adequate force, the wood containing hidden knots, or the length of wood being too long. Unlike an axe, mauls are effective longer after the edge dulls, as the primary mechanism is that of a wedge pushed through along the wood grain, and not a cross-grain chop of an axe. In some cases, longer logs may be split while they rest length-wise on the base or ground. Mauls often become stuck in logs mid-split requiring a "full-lift" chop to be used. This involves the chopper reswinging the maul, but this time lifting the half-split log while still attached to the embedded maul, often requiring one or two additional full-lift chops. Another technique for splitting upright logs of thicker diameter is to land the maul's full force off-center of the log, usually removing 1/4 of the mass of the log. When repeated, large logs that would ordinarily cause the maul to be embedded on a center-strike can be handled easily. Additionally, as the temperature gets colder, the fibers in the log become more brittle making the logs easier to split.