The surprise attack zombies can also be referred to as Ambush Zombies and usually come in sets of three; They emerge from graves at Night, emerge from the pool in the Pool and Fog levels, and are dropped down by Bungee Zombies on the Roof (Night levels are the exception of the "come in sets of three" principle, as there are always more than three graves). The Ambush Zombies can be normal Zombies, Conehead Zombies, Buckethead Zombies, and their Ducky Tube Zombie forms, with the exception of Level 5-5 and its mini-game version.