I already know exactly how to code the spell to do damage in a line, but it is impossible to make MUI.
All I need is how they make the spell MUI.
My problem is with my spell Infernal Wave, it causes damage in a line.
I make it pick all enemy units in 200 range of the projectile and do the following:
Deal damage
Add unit to "was hit" unit group
I can't have it MUI if the "was hit" group is a global variable (I am not going to make an 8192 array for it). But there is no way I can see, even with hashtables, to make it MUI. Since the hashtable unit group handle must refer to a global unit group.
For now, I have it MPI with "was hit [number of triggering player]" but this is still half-assed and it must be MUI if at all possible.