Zombie Master is a multiplayer Source modification, centred around a zombie-apocalypse, which throws all but one player in the shoes of human survivors. Pitched against a relentless tide of rotting flesh, they must scavenge for weaponry and equipment just to stay alive. But that one player, chosen randomly at the beginning of the round, is not bound by mortal restraints. To speak his name is to invite the wrath of hell - but most call him the 'Zombie Master'. He is nigh omnipotent. His invisible hand controls the legions of undead like puppets on strings; slowly closing the net on the humans while they run to and fro like rats in a maze.
Zombie Master is one of my old favorites. The notion that one player truly can screw over and control the experience for a team of humans as they complete dynamic objectives is just as fun as it sounds. Sadly, the community has all but died at the point of this review, but a remake/sequel is in the works by a separate modder.
ZM in its hay day was some of the most genuine fun you could grab out of a mod.
An entirely original mod that seperates the two sides: the Survivors and the Zombie Master, who can control the zombies as they spawn and use traps (depending on the map) on other players. It was a blast to play with friends, as long as the servers were up. Right now it can still be just as fun, but only as long as there are others to play it with. I suggest you grab some friends, start a server and play several rounds.
All in all, Zombie Master has always been and always will be a personal favorite. It's the game you remember, but it's the times that have changed.
It's new, and it doesn't actaully feel like a retextured hl2, which is what most mods I've played are like. That, and the game itself is fun. Need I say more? I think this actually changed the market, and if you don't believe me, look up the SmartGlass trailer for PvZ Garden Warfare. That's just one example. This is a huge game, and if it were on Steam as a published release, I'd buy it.