[Agema]

There's range, and area of effect.

Range is how far something can happen - 25 squares is 25 squares from the source.

Area of Effect is slightly different, I think it means that it affects a certain number of squares within a certain area of the centre of effect. So for instance a spell or effect with AoE 6 will hit 6 squares, but precisely what squares are hit may vary - it could be six of a block of nine (the central square and randomly 5 of the 8 surrounding the central one). But someone else might be able to explain better.