Valve continues their awesome L4D2 support with Week 15. This week’s Xbox 360 mutation is the encore mutation “Four Swordsmen of the Apocalypse”, which features all 4 Survivors facing constant streams of Special Infected with nothing but Katana’s, and this week’s PC mutation is also an encore mutation. “Versus Survival” is essentially the classic Survival gamemode, except the Special Infected are controlled by players. The voting breakdown for the two platforms was: