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Zombiecraft Server

Zombiecraft is a Minecraft server that gives you a cool zombie survival experience. If you like zombies, this is the place for you. You can play with up to four friends fighting against waves of zombies. As you survive, you can unlock new parts of the map and find better gear from mystery boxes, perk machines, and wall weapons. Keep barricades up to slow down zombies and protect yourself and your friends. Try to survive as long as possible before the zombies get you. And guess what? This server works with regular Minecraft, so no need for mods. Just jump in and start killing zombies.

(Source: Zombiecraft)