The healing boon has a random effect. This means, even on an exceptional attribute roll, the healed damage can still turn out to be 1 – what a let-down. So: what are the pros and cons of changing the heal boon to heal a fixed amount of damage? What about persistent damage and regeneration?
Hmm well, personally, I really like the random aspect of damaging and healing boons. It gives a lot of flavour options to the GM.
If you really want fixed values, you can use the same method as D&D, which is giving the average outcome. So, for example, the Heal boon at PL 1 would heal 1.5 hit points (normally 1d4), probably rounded up to 2.
I think it makes the game a lot simpler if you do it this way, so I think it’s worth trying it in your games.
average of a d4 is 2.5, however, dice explode in OL. So yes, you can roll a 1, but you can also roll a 25.
Also, in OL, you can keep invoking it, whereas in dnd you have a limited amount of spells you can cast.
Yeah, heal even says explosions still count. 1 out of 4 chance the lowest heal will be at least 5, and being able to invoke limited only by time, not by resources, lets you keep trying and spend a while at it.