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This battle takes place on top of a incomplete skyscraper. Beetle has three different attacks: His laser blasts (used for far rage), Laser sword (used for close range) and his shield (used as a counter against combos).

First thing, switch your special to adrenaline. Now he should start off blasting at you with his multi-directional lasers flying in the air. You can't dodge these blasts so don't try. All you have to do to avoid these is run back and forth under him. Whenever you see an opportunity, jump up and start beating him with air combos. If your Spider Sense goes off while doing this simply jump away to avoid his Shield move. Repeat this until he starts getting close to the ground. At this point you should jump over his beams until you're up close enough to uppercut him (Up+Punch). do this three times in a row and then move away from him. Then use the adrenaline rush whenever you can and he should be taken down fairly easily.