Don't get into critical condition, it usually means game over...

Destroying parts, defeating enemies, breaking gauges refill bezel. Scratch damage heals over time too, a long distance IS can heal like 1/4 or 1/3. If one member is gang bang by multiple enemies, IS away if you can, concentrated firing must be avoided. Sending strong enemy to the air or smack down them will break their attack, can be life saving sometimes. Try to make use of these basics, then you can devise your own strategies

how to do smackdown..
at arena and already f***up..