Summon

Summons are cards that, like Buildings and Spells can only be played once the game has reached a certain time, depending on their Stage and paying with Mana.

Summons can only be placed within the green spawning areas, in range of your Nexus or one of your Lanetowers.

Most summoned units have when you summon them, this makes the increases the risk when you summon new units too close to the enemy because they will be  and take increased damage.