Do spells stack when placed on top of each other?

Solution 1:

Spells don't stack, but they do work together in a way. At least some of them do.

Lightning spells deal set damage. So you just deal the damage from two if you use two, no multiplier.

Heal spells are not actually time dependent, but hit-points healed dependent. So placing two down will, from a point of view, stack. The units gain double benefits, but not more than that.

Rage spells don't stack in any way, they are time dependent. The only reason to overlap them is for continued rage.

Jump spells are just like rage spells, they're time dependent, and there's no benefit to overlap except for allowing units to move further

Freeze spells are also time dependent, so same deal.

So essentially it's just heal spells.