Serious Sam
Complete the game in single player on serious difficulty.
30 ✓ July 10th, 2010
Game Master
Complete the game.
20 ✓ July 10th, 2010
Serious Beginner
Complete any level in single player.
10 ✓ June 12th, 2010
Co-op Hippie
Complete The Great Pyramid in co-op with blood option set to hippie.
10 ✓ June 13th, 2010
Cannon Expert
Pierce at least 10 enemies with a single cannonball.
5 ✓ June 13th, 2010
Co-op Beginner
Complete any level in co-op.
5 ✓ June 12th, 2010
Serious Co-op
Complete a co-op game on serious difficulty and extra enemy strength on 400%.
35 
Look, It's a Secret
Find at least 50 secrets in single player.
30 
Metropolis King
Complete Metropolis level in single player on serious difficulty without loading.
20 
Serious Run
Complete the game in single player by beating estimated time on each level.
15 
I am Invincible
Complete the game in single player without firing a single bullet or shell.
10 
Perfect Kill
Kill all enemies in Karnak in single player.
10