During the day you build towers, mines, walls, and upgrade your spells at your own pace. When you're ready, start the night. Enemies will flood toward your emitter and test your defenses.
There are 15 unique towers, each with different upgrades and attack modifiers, that can be placed freely on the map to create any shape of maze.
Units tunnel-vision straight toward your emitter — unless you crank the signal high enough, at which point they start attacking your towers. Survive until morning and any lost towers are automatically restored.
Each run begins by choosing a starting spell that shapes your entire strategy:
Tower Tail: Your builder leaves behind a tail of random towers when moving — great for reshaping the maze while enemies are mid-path.
Spirit Link: All towers attack through your builder, giving the game a strong bullet-heaven feel.
Layman's Lift: Tower upgrades are stronger, at the cost of not being able to use spells.
Beat all nights of a level to progress through the campaign. After winning, continue to the next level or keep playing in endless mode, a never-ending onslaught of procedurally generated waves that will push your strategy to its limits. Chase the highscores of other players and see how far you can go.