AoE

These effects trigger on an area, instead of on an individual unit.

Overview
AoE or Area of Effect is a term to describe spells or attacks that affect units in an area as opposed to a single unit. These are inherently more powerful than single target attacks or spells, and are therefore much more costly. Additionally, the effect on each individual unit is usually weaker than the change that a single target attack or spell would have, to compensate for the inherent strength of being able to affect more than one unit at a time. A subset of AoE effects is referred to as Splash. Splash effects are more powerful in the center, and lose their effectiveness gradually as the area expands.