I'm doing something like this with events. It was supposed to be something for my server only, but I guess I could tell...
Materials (Mods):
Left4Block
Set Player Apperance/Set Player Color
Agile Playertype
Minigame++
Teleport event (Not sure what it's called)
Fist (Weapon)
Midevil-Armour Playertypes
Steps:
1. Create a level with a 1.Saferoom, 2.Zombie(Bots) Spawn, 3.Spawn-room for Zombies(Humans) separate from the rest of the level.
2. Use Minigame++ to create a team DM. Team 1 will be the survivors, Team 2 will be zombies. Have players spawn as the Standard Playertype.
3. In the Saferoom, wrench the spawn points and make the event say:
<onRespawn> <Player> <ChangeDatablock> <SurvivorPlayertype>
Repeat for all spawns.
4. In Human-Zombie Spawn room, create 4 bricks. Each brick will be a different zombie. Make one brick:
<onActivate> <Player> <ChangeDatablock> <AgilePlayertype>
Then set your appearance and color to look like the Hunter and use the setColor and setAppearance events. Then use the setInventory event to set the weapon to the Fist.
5. The Boomer and Smoker are up to you, that is, deciding how to make the player function like them.
6. For the tank, have the events read:
<onActivate> <Player> <ChangeDatablock> <(The Strongest Armour Playertype)>
Then have it set the scale to +2.0.
There you have it!