When elco gets lock inside krenns central processing unit there will be a save spot there, once uve saved use the elevator to go down, once ur down krenn will fight u, use the ion flxinator weapon cuz it deals big damage,move bakwards while shooting when krenn goes near you and tries to hit u with his leg, when he goes back he might use the laser cannon, i suggest u get closer to krenn and start shooting while his beam keeps chasing u, when the beam stops he would attack u again and shoots the beam again until he runs low in hp, when he tries to heal avoid the suicide droids and destroy the charger that heals krenn, after that krenn will attack u again, after a series of healing krenn will malfunction when his life gets really low, he will spin crazily when he gets near you so avoid that, keep shooting with the ion fluxinator antil krenn explodes into a million gigabytes, follow this and you can kill krenn easily :)

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Love what you do." :)