Now you don't need to buy Left 4 Dead 2, see.

BFG gathering dust? Get your fingers into Skull Tag, an intimidatingly well-equipped “sourceport” of Doom II, featuring new items, bots, modes, weapons, maps and at least two or three kitchen sinks.

It’s classic Doom gunplay with the addition of jumping and freelook. New modes include “Invasion”, a wave-based defensive affair, “Possession”, in which players score points by keeping hold of a Hellstone for as long as possible, and “One Flag CTF”, which is like CTF except you have to return the flag to your opponent’s base, rather than your own.

In a departure from the original Doom II, you can drop in and out of games in progress. There are no dedicated servers. Time for another petition, Modern Warfare 2 fans?

Blurb here, download here, installation FAQ here, screenshots here. You’ll need a copy of Doom II, Heretic or Hexen.

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