SPOILER ALERT!!
In the native game, you need to unlock some of these items before you encounter them, so much of this information is a spoiler.(infinite ammo)1. Plasma Pistol: Unlocked from start2. Blast Pistol: Unlock: Kill 30 Drones (rest every 3 shots)3. Laser Pistol: Unlock: Kill 50 Elite Guards (3 shots timed recharge)4. Compound Bow (Mutator-Only) 5. Super Shotgun: Unlocked from start (2 shots)6. Bouncer Shotgun: Unlock: Kill Accountant 5x (5 shots)7. Dart Gun: Unlock: Beat Damage Amplifier (7 shots) 8. SMG: Unlocked from start (14 shots)9. Assault Rifle: Unlock: Kill 50 Guards (30 shots)10. Revolver: Unlock: Kill Dr. A. Morral 3x (6 shots) 11. Rail Gun: Unlocked from start (4 shots)12. Laser Rifle: Unlock: Kill 30 Stalkers (100 shots)13. Sonic Pulse Generator: Unlock: Silver trophy+ on all non-boss enemies (9 shots) 14. Grenade Launcher: Unlocked from start (1 shot)15. Rocket Launcher (RPG): Unlock: Kill 30 Security Tanks. (1 shots)16. Sticky Grenade Launcher: Unlock: Kill 25 Kamikaze Drones. (3 shots)