Defense Grid - PC Battle 15 different enemy types that become increasingly stronger, and employ a variety of strategies in an attempt to bypass the players defenses. Utilize 10 different tower types with 3 levels of capability each. Each tower has unique tradeoffs that affect ideal placement, such as line-of-sight attack or ballistic trajectory fire; a large area of effect or damage over time High Replay Value -each game level can be solved in many different ways, with increasing rewards for improved efficiency Explore 20 unique environments, each with a different placement of roads, tower build locations, and open areas to plan a strategy around Battle 15 different enemy types that become increasingly stronger, and employ a variety of strategies in an attempt to bypass the players defenses. Utilize 10 different tower types with 3 levels of capability each. Each tower has unique tradeoffs that affect ideal placement, such as line-of-sight attack or ballistic trajectory fire; a large area of effect or damage over time High Replay Value -each game level can be solved in many different ways, with increasing rewards for improved efficiency Explore 20 unique environments, each with a different placement of roads, tower build locations, and open areas to plan a strategy around