Use PK on each Monolith pillar (the spinning things). Upon destroying them you can collect up to six orbs (which will be scattered around the room) for your new psionic weapon. Once The General gets to full health, the fight will begin. Just shoot him with the psionic weapon to damage him. You can refill your psionic weapon's ammunition by getting in the center of the Monolith. Note: Make sure to quickly get out from the Monolith once your ammunition is refilled. Also, when The General goes invisible, just use your Aura View to see him.