For a game like Zero Hour , a trainer might freeze the value of your in-game currency (Supplies), ensuring you never run out of money to build tanks and aircraft, or it might make your units invulnerable to enemy fire.
By default, the Particle Cannon (USA) or SCUD Storm (GLA) has a 5-minute cooldown. The trainer removes this cooldown entirely. You can blanket the map in nuclear fire or Anthrax Beta clouds continuously.