When cast, a boulder is spewed in front of the caster. The boulder travels a short distance before falling to the ground. It explodes upon colliding with an object, dealing moderate physical damage in a small area around the point of impact. Some opponents may also be launched away from the blast radius.
When used against blocking opponents, the boulder's impact causes large stamina damage, potentially breaking their guard. As such, the player may be able to follow up casting this pyromancy with a guard break attack, causing significant damage to the enemy.
Due to its low requirements and FP cost, Boulder Heave is a very effective pyromancy if used correctly. It can stunlock certain foes and is one of the few ways of reliably hitting enemies that are climbing up ladders. The pyromancy's area-of-effect means that it can be an effective way to deal with tightly-spaced groups of enemies.
Its low FP cost and ability to inflict large amounts of damage also makes the spell useful for PvP. The slow casting time may allow an opponent to interrupt the casting easily; however, as casting, it does not provide Hyper Armor.