There are a total of 5 weapons which are unlocked by making significant progress through the main story of the game, as they are as follows:
- Vulcan Gun
- 60mm Cannon
- CPU Virus
- Missile Barrage
Once you have all 5 weapons unlocked, go to AR Challenges and select "One Man Army" and use each one in this battle. Keep in mind the the CPU Virus, EMP and Missiles require 1 bar of energy to be used. The trophy unlocks as soon as all 5 weapons have been used.