The Mercy is not constructed by a missile launcher. Instead, any Aeon factory that can construct a T2 Air Unit can also construct the Mercy. It fires a swirling cluster of bombs which are so volatile that launching them destroys the Mercy. The bomb does 2400 damage over a significant area of effect, making it effective at destroying both moving armies and tight clusters of buildings. Although it has low HP compared to other tech 2 air units, this isn't much of a drawback because it only needs to get close to its target once.