|This is a spiritual successor to Zombie Panic: Source, a popular Half-Life 2 mod created by Monochrome. At face value it’s easy to look at Contagion and write it off as a Left 4 Dead clone. But Contagion—also a source-based shooter—emphasizes a starkly different style of play compared to Left 4 Dead.
Where as Left 4 Dead is a frenetically paced, horde-blasting, bullet-spraying shooter, Contagion sticks more closely to “traditional” zombie apocalypse and survival horror roots. The common traits of zombie shooters are still present—there more zombies than there are survivors, zombies want to eat you, and you will need to defend yourself with a variety of firearms.
But given Contagion’s more “traditional” survival horror approach to the Zombocalypse, it uses an ‘iron sights’ aiming method, which slows your movement to improve accuracy at the expense of movement speed. Headshots are vital to survival and conserving precious ammo, which is in short supply.
And while there are plenty of variant zombies, unlike Left 4 Dead there are no ‘special’ zombies in the game with weird, mutated powers.