Rift

Endless waves after chapter 1. A run costs 10 energy. Your HP carries over between waves, you heal 15 % after each one. Foes grow 15 % per wave, every 5th wave is an elite (×1.5). Each wave banks 40 gold × wave number and 25 EXP × wave number. Retreat in time: what you banked is yours, a defeat ends the run.