Collect all trophies
Complete all six chapters in Part 1
As host, complete a rescue mission for all four locations in Part 2
Find all 18 signs in all 6 chapters in Part 1
Find 9 signs in any three chapters in Part 1
Find all 3 signs of a single chapter in Part 1
Kill all enemies during Hardboiled's final, successful escape in Chapter 6
Drop six Space Owls into the liquid ooze in Chapter 6
Defeat the swinging hexapod, once you see its health bar, in under 30 seconds in Chapter 5
Stand on the Hexapod's Nose while it is firing its missiles in Chapter 4
Detonate a bomb near either G-man in the final show-down in Chapter 2
Make enemies kill 15 co-workers in Chapter 2
Melee kill 15 Enemies in a row without triggering the alarm in Chapter 2
Headshot kill 15 enemies in a row in Chapter 1
Get someone to tell you what's up ahead in Chapter 1
Make Putzki shoot himself in Chapter 1
Unlock 100 costume items or weapons in Part 2
Attain 3 star scores for all four locations in Part 2
Attain a 80% or higher accuracy score on a mission in Part 2
As host, collect all nine artifacts in Part 2
Unlock all 4 hostages in the UFO in Part 2
Unlock all 4 hostages in Jungliana in Part 2
Unlock all 4 hostages in Putzki's Pork Plant in Part 2
Unlock all 4 hostages in Putzki's Castle in Part 2
Spend more than 50,000 bucks in Part 2
Headshot kill 100 enemies in the game
Melee weapon kill 100 Enemies in the game
Kill 4 Enemies with a single grenade shot in the game