How to doctor: Smash away his ribs with a hammer, pull out ribs and lungs, smash a beaker, grab a glass shard, cut out old heart, pick it up, and throw it somewhere, punch open new heart container, grab new heart, drop it in chest. My work is done.
Tips:Collect the power up tokens (red,green,blue and purple circles) to increase fire rate,damage,and bullets fired.A good combo is lasers as secondary and classic as your main.First box of adrenaline is a shield,two boxes is slow-mo,three or more is special.