Corruption is a Common Instant Spell belonging to the File:Icon Chaos.png realm. It may only be cast on the overland map. For the base Casting Cost of File:Icon Mana.png , it will cause Corruption in the targeted tile, completely disabling any benefit this tile gives to any nearby Town. Corruption can be undone in several different ways, primarily through Purification by special units. There is no need to maintain the resulting Corruption with magic, so the Corruption Spell has no Upkeep Costs.