Vatn is a unit original to Metal Slug Attack, first appearing in the Extra Ops titled Halloween Train (as a pre-acquisition unit, obtained by purchasing 10,000 medals). He serves as an expy of Van Helsing. If Vatn is defeated, he will grab a bomb from his coat and ignite it as a parting gift. Upon exploding, a medium-sized projectile will fly in a smaller arc, dealing massive damage to enemies hit by it. A 15% AP cost discount applies to Vatn if placed in a deck with Emain Macha and the Subway, as part of the "Halloween Train" team bonus.