You have to get close to him and spin arpound with him. Get in the armpit of that blue blade and its actually his easiest attack to evade. There are alot of others from which there is no where to hide.
Anway Im starting to get convinced that he cant be beaten while carrying the warp core. Guess I will never know what the final upgrade is... :(
Used davidcd's suggestion and went with plasma and Splash and beat Atropos, but I cant beat him with out using a shield and defencive laser, which means I stille havent recharged my warp core.
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