Quick design changes and bugfixes — Heat Death Steam update #1829013

- Combust's damage should now be handled mostly in the same way as ordinary attacks, benefitting from Firepower and modifiers. - The tech "Explosive Supplement" has been removed from the reward pool, because its effect is now redundant. - fire attacks, dark attacks and Plasma attacks are now affected by Mystery. This will cause more ticks of Burning, more Shieldpower reduction, and more max health reduction when combined. - the "Coating" buff should now correctly reduce the damage of Burning. - Other minor improvements and bugfixes