KT-4

The KT-4, also known as the Kusanagi-no-Tsurugi is a buildable Wonder Weapon that appears in the map Zetsubou No Shima. It's capable of releasing a green liquid that makes spore bags grow on their bodies and make them explode. For a better and more lethal shot, the player has to hold down the trigger, if done so, the liquid will stay on the floor, and affect any enemy that goes over it.