Mouse - building towers, Arrows/WASD - moving hero, 1-8/Mouse_wheel - changing weapons, Space - Forge, rftgyhuji - shortcuts for building towers, Holding Shift - makes game faster, P - Pause.
Hero Tower Defense.
There are two playable heroes on the map that will assist you in your defense. 60+ unique towers are divided into 9 groups. You can upgrade towers, and sell towers that you don`t want anymore. Be careful with roads, because enemies will build their own roads over time.