I've already killed the last boss of the insane campaign 5 times. The first time was difficult.
Each of the mechs consumes almost a lifetime of my mech, so you need 3 life improvements. And 20 tokens to revive 2 times.
This is the mech I use for the campaign. The heat kills them easy. It has heat drone too & heat hook.
This mech is for the campaign only. It is very bad to use in battle.
If you haven´t the new cooling module, you can put 2 Heat Controls either or whatever you have. Although it will lower your life a little.