Fix ground target aoe for Y-axis.

I have no clue about coding or how this function but I doubt it's intentional and if it is, it's stupid.

Mostly notice this for Ground target aoe spells will not hit mobs if they are on a different level on the Y-axis even though the mobs are WELL within the aoe.

Maps like Steppe it's extremly noticeable and I don't see the logic in standing on higher ground casting aoe spells that literally fills en entire screen but mobs that stand lower than me and vise versa on the Y-axis doesn't get hit.