How to get more stuff? Actually, you can do the following tasks and get the indicated results:
Last Call/10 pts: Beat the Last Call level
Escape Velocity/10 pts: Beat the Escape Velocity level
Downward Spiral/10 pts: Beat the Downward Spiral level
Rites of Passage/10 pts: Beat the Rites Of Passage level
Second Chances/15 pts: Beat the Second Chances level
All Fall Down/15 pts: Beat the All Fall Down level
Crash Landing/15 pts: Beat the Crash Landing level
Sacrifices/20 pts: Beat the Sacrifices level
There Are Others/20 pts: Beat the There Are Others level
Guiding Fires/20 pts: Beat the Guiding Fires level
The Old Tribes/25 pts: Beat The Old Tribes level
Hidden Agenda/25 pts: Beat the Hidden Agenda level
Jen/25 pts: Beat the Jen level
The Dark Harvester/30 pts: Beat The Dark Harvester level
Following Her/30 pts: Beat the Following Her level
The Complex/30 pts: Beat The Complex level
Ascent/40 pts: Beat the Ascent level
Center Of Gravity/40 pts: Beat the Center Of Gravity level
Resolutions/40 pts: Beat the Resolutions level
Oath Of Vengeance/50 pts: Beat the Oath Of Vengeance level
Facing The Enemy/50 pts: Beat the Facing The Enemy level
Mother's Embrace/60 pts: Beat the Mother's Embrace level
Savior/65pts: Beat the game on the Normal difficulty setting
Galactic Hero/65 pts: Beat the game on the Cherokee difficulty setting
Young Blood/10 pts: Get 50 total kills in Death Match
Brave Star/15 pts: Get 125 total kills in Death Match
Ultimate Warrior/50 pts: Get 500 total kills in Death Match
Team Member/10 pts: Get 50 total kills in Team Death Match
Team Player/15 pts: Get 125 total kills in Team Death Match
Team Leader/20 pts: Get 250 total kills in Team Death Match
Sharpshooter/10 pts: Get 25 sniper kills in Death Match and Team Death Match
Invisible Assassin/10 pts: Get 25 kills in Death Match and Team Death Match using spirit form
Mechanic/10 pts: Get 25 kills in Death Match and Team Death Match using the wrench
Rifle Ranger/10 pts: Get 25 kills in Death Match and Team Death Match using the rifle
Crawler King/10 pts: Get 25 kills in Death Match and Team Death Match using Crawler grenades
Machine Gun Tommy/10 pts: Get 25 kills in Death Match and Team Death Match using the Auto-Cannon
Launcher Lord/10 pts: Get 25 kills in Death Match and Team Death Match using the Crawler Launcher
Soul Sucker/10 pts: Get 25 kills in Death Match and Team Death Match using the Leech Gun
Toxic Overlord/10 pts: Get 25 kills in Death Match and Team Death Match using the Acid Sprayer
Rank 1/20 pts: Win a ranked match
Ten Ranked Matches/20 pts: Play ten ranked matches
Black Jack/10 pts: $250 won on Black Jack
Poker Face/10 pts: $250 won on Draw Poker
Retro Gamer/10 pts: Score over 15,000 on Runeman