Then just make your trigger heal allies? If you don't have a clue how to heal allies, then your spells are certainly lame, flashy can be lame too, you know.
If you really want to know how to do that, it's like this: create a unit group (variable) named HealingGroup (for example). Then when you want to heal allies, just use "Pick every unit in group and do actions" action and heal them the way you healed...........Heal_Ward_Formation?? Didn't you say that Heal_Ward_Formation is a spell?? You know, you're the first one who managed to HEAL A SPELL!!!! That variable is not a spell, it's a unit, so I'm asking you again, what is Heal_Ward_Formation?