Unlock the following Avatar Awards by performing the corresponding tasks:

AVATAR AWARD - HOW TO UNLOCK
Doom 2 Marine Suit (male or female) - Complete the "No Rest For The Living" episode in single player mode.
Doom 2 T-shirt (male or female) - Finish a level in single player mode. 

Just Getting Started (10 points) - Complete any level in Single player.
Rip and Tear (20 points) - Complete any level on 'Nightmare' in Single player.
Superior Firepower (25 points) - Complete all levels on 'Ultra-Violence' or higher in Single player.
An Important Looking Door (10 points) - Find a secret area of a level in Single player.
From Earth To Hell (25 points) - Complete all levels in 'Doom II - Hell on Earth' in Single player.
And Back Again (25 points) - Complete all levels in 'Doom II - No Rest for the Living' in Single player.
Burning Out of Control (15 points) - Complete any level with 100% kills, items, and secrets in Single player.
Destroyer (20 points) - Get 100 frags in Deathmatch on Xbox LIVE.
The Great Communicator (10 points) - Get 20 kills using the Chainsaw in a single level in Single player.
A Man and a Half (10 points) - Get 20 kills using the Berserk Powerup in a single level in Single player.
You Have Huge Guts (20 points) - Kill a CyberDemon using your fists in Single player.
A Really Big Gun (10 points) - Find a BFG in Single player.