The spiritual successor to Left 4 Dead released back in October last year for PC, PlayStation and Xbox. By the end of that month, it had six million players already - no doubt boosted by its arrival via Xbox Game Pass. Today also brings word of Tunnels of Terror, a “major” expansion set to arrive on 12th April as part of the game’s Annual Pass. This adds a new PVE activity, fresh Cleaners and Ridden variants and yet more character and gun skins. Ridden Hives, the expansion’s new PVE mode, is a four-player co-op dungeon crawler feature seven different labyrinths to explore. It’s here you’ll find the new Warped Ridden enemy, which will also be added to the PVP Swarm mode. Two new playable Cleaners (Sharice, “an axe-wielding firefighter” and Heng, “a no-nonsense restaurateur”), 12 weapon skins, eight character skins, seven new legendary weapons, and one new difficulty setting: No Hope. In a nice move, only one person in your co-op party will need to own the Tunnels of Terror expansion for all players to access its content. Turtle Rock today committed to not adding new microtransactions to the game as part of the expansion, either - or via any future content update.