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Rather than being visible at all times, Brolders hide underground until they are approached, at which point they will slowly emerge from the ground. Brolders' only method of attack is rolling in the character's direction to harm them. However, when they are hit by an attack or tapped on the GamePad, they temporarily become common boulders with no eyes or arms. In this state, they can be picked up and carried by the player, then tossed in a preferred spot. In a section of Mystery House Marathon, Brolders must be placed onto switches to keep them simultaneously pressed, granting a Green Star. Brolders can be defeated by being tossed into the lava or by having another Brolder tossed at them.
If a Brolder is not attacked periodically while in its boulder state, it will start to rumble and eventually turn back to normal, beginning to roll towards the player again. If a player is holding a Brolder when this happens, they will take damage before dropping them.
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