Small Arms
- Play as Billy Ray Logg
- Defeat Billy Ray Logg in Mission mode to unlock him.
- Play as ISO-7982
- Successfully complete Mission mode to unlock ISO-7982.
- Play as Mousey McNuts
- Defeat Mousey McNuts in Mission mode to unlock him.
- Play as Professor Von Brown
- Defeat Professor Von Brown in Mission mode to unlock him.
- Shooting Range
- Successfully complete Mission mode to unlock the Shooting Range.
- Hidden targets
- If you jump up and climb on top of the third row of targets at the Shooting Range you will be able to see a third row of targets. A bullseye on one of these is worth 5,000 points.
- Achievements
- Accomplish the indicated achievement to get the corresponding number of Gamerscore points:
- Completed Training (10 points): Complete the Single Player training mode.
- Combo x2 (15 points): Kill two opponents in rapid succession.
- Combo x5 (20 points): Kill five opponents in rapid succession.
- Challenge x15 (10 points): Defeat fifteen opponents in Challenge mode.
- Challenge x50 (25 points): Defeat fifty opponents in Challenge mode.
- Won 10 Matches (10 points): Win ten matches in Single Player or by playing on Xbox Live.
- Won 50 Matches (15 points): Win fifty matches in Single Player or by playing on Xbox Live.
- Won 100 Matches (25 points): Win one hundred matches in Mission Mode or Battle Mode.
- Complete Mission Mode (20 points): Complete Mission mode.
- Played 100 Matches (25 points): Play 100 matches either offline or on Xbox Live.
- Marksmanship (25 points): Score over 10,000 in the Shooting Range.
- Six Degrees of Small Arms (0 points): Obtained from a special player online.