Totally Accurate Battle Simulator is a strategy, physics and simulation game that is currently free on Epic Games. Expires 26th December at 16:00 GMT.
Description:
Totally Accurate Battle Simulator is a wacky physics-based tactics game. Experience accurate warfare through the ages. TABS uses state of the art physics-based simulation to provide you with never-before-seen insight into our greatest battles of history!
Link:
https://www.epicgames.com/store/en-US/product/totally-accurate-battle-simulator/home
Enjoy and Merry Christmas. 
