These are all from the 360
Assassins Creed
Keeper of the Four Gospels - You've collected every Jerusalem Flag.
Keeper of the Order - You've collected every Templar Flag in Acre.
Keeper of the Black Cross - You've collected every Teutonic Flag in Acre.
Keeper of the 8 Virtues - You've collected every Hospitalier Flag in Acre.
Keeper of the Crescent - You've collected every Damascus Flag.
Keeper of the Lions Passant - You've collected every Flag in the Kingdom belonging to Richard.
BioShock
Brass Balls - Complete the game on Hard difficulty without using a Vita-Chamber
Mass Effect
Turian Ally - Complete the majority of the game with the turian squad member
Krogan Ally - Complete the majority of the game with the krogan squad member
Sentinel Ally - Complete the majority of the game with the Alliance sentinel squad member
Soldier Ally - Complete the majority of the game with the Alliance soldier squad member
Quarian Ally - Complete the majority of the game with the quarian squad member
Asari Ally - Complete the majority of the game with the asari squad member
Call of Duty World at War
Hardened War Hero - Completed the game on Hardened or Veteran difficulty and won on all fronts. (Veteran)
Here is a list of my 100 percent completed games including their DLC. All on Xbox 360
Alan Wake - 1500/1500
Assassins Creed - 1000/1000
Assassins Creed 2 - 1000/1000
Avatar The Burning Earth - 1000/1000
Batman Arkham Asylum - 1000/1000
BioShock - 1100/1100
Borderlands - 1750/1750
Call of Duty 4: Modern Warfare - 1000/1000
Condemned - 970/970
Condemned 2 - 1000/1000
Dead Space - 1000/1000
Fallout 3 - 1550/1550
Far Cry 3 - 1000/1000
King Kong - 1000/1000
Lego Batman - 1000/1000
Lost Via Domus - 1000/1000
Madden 06 - 1000/1000
Madden 08 - 1000/1000
Modden 09 - 1000/1000
Marvel Ultimate Alliance - 1000/1000
Mass Effect - 1000/1000
MLB 2K6 - 1000/1000
MLB 2K7 - 1000/1000
Modern Wafare 2 - 1000/1000
NBA 2K6 - 1000/1000
NBA 2K7 - 1000/1000
NBA 2K9 - 1000/1000
NCAA Football 09 - 1000/1000
Elder Scrolls 4 Oblivion - 1000/1000
Sherlock Holmes - 1000/1000
The Walking Dead - 500/500
TMNT - 1000/1000
WWE Legends - 1000/1000
I am close on a bunch of games though like Mass Effect 2, Mass Effect 3, Dishonored and a few others.