Resin

"The events unfold in a dying world, dominated by machines and artificially created lifeforms. Warmth generators, the very last remaining living creatures in the world are used by machines as energy sources. You control an android woman made out of Resin, who was programmed with a task to slay the Warmth generators. Ironically, without their vital energy her life would also fade away."

"Resin is a tough as nails 2D action-adventure with heavy emphasis on fighting. It has regressive leveling system, which means that every time you win a boss fight your character will become weaker, forcing you to adapt to new play styles and try out new strategies. It features a branching open world, multiple endings and bosses with different mechanics."