The Urban ReDuel Multiplayer Map Pack Add-on for TimeShift has 5 achievements worth 125 gamerscore.
Use rocket launcher 11 times to kill opponent while he is in the air. Low gravity mode will help.
Use time powers or time fields to prevent falling damage 3 times.
Throw reverse grenade when opponent is shooting you. Kill your opponent 3 times with his own shots.
Use your time shield to escape from any time field 25 times.
Win ranked match on every map in DLC 2.