You are the last surviving member of a SEAL team sent into Russia. Fight off waves of invading enemies and survive for as long as you can. Start out with a pistol and a few grenades, but scavenge new weapons from fallen enemies to build up a deadly arsenal.
Fight off waves of creepy monsters by placing a defense of attack towers. Earn money from kills to buy new towers, upgrade them, and also purchase various element shards to give your towers special abilities.
Start out as an old man looking for a way to turn back time and restore his youth. Explore the world and look for ways to get younger with each step backward in time granting you the ability to jump higher and move faster.