Wallhacking, Wallhack or wall hack is the change of wall properties in first person shooter games. Most wallhacks are used to make a map of walls, at least partially transparent, allowing players to see through opaque objects. Wallhacking is usually considered cheating, analogous to maphacking in real-time strategy games, and can lead to kickeos and banning of online game servers if it is discovered.
Many of the FPS games provide weapons like grenades that can kill hidden players, but these types of explosives have splash damage instead of direct hits. However, in a game like Call of Duty 4: Modern Warfare, certain guns can shoot through walls, guns, in particular. This allows them to see the enemy and kill instantly, without being seen. Other types of wallhack include "wallwalk", in which players can see and walk through the walls. Sometimes called "ghostmode", this hack allows hacking attacks on anyone walking on the wall, when the player inside the wall is essentially invisible.
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