Each Spell Card is given a Mastery score, from 2 (easy) to 4 (hard). This can also be applied to spell-like artefacts. Scrolls and other such one-shots, have a Mastery score one lower than normal.
Things like Healing spells and the Genie’s attack are 4’s, things like Clairvoyance are 2’s, and you can even put really basic stuff, like the Genie opening a door, at 1!
When a Hero wants to cast a spell, they roll a number of D6 equal to the Mastery of the Spell. If they roll less than their Mind, the Spell works. If not, tough, you’ve wasted your action, but nothing is discarded. Effects like the Elf potion that allows the spell to be retained after casting, instead allow you to roll one fewer D6 when attempting to cast a specific Spell.
The starting Wizard will mostly get 2’s to cast (just under 50% of the time, have difficulty with 3’s, and struggle with 4’s.
This also makes MP important to the Wizard beyond defence against Chaos Spells, which will have their Mastery at one point lower than the equivalent Hero Spells.
Mastery number off the top of my head. You will note that I gave a fourth spell to each group, as a variant of one of the Spells. This was to accommodate spells with multiple uses, but lead to a few ideas elsewhere, and I had to create some. I also adjusted the healing spells to allow for the fact that the Wizard especially can get them off more than once!
Tempest: 3
Swift Wind: 2
Efreet (Genie, Attack): 4
D'Jinn (Genie, Door): 1
Rock Skin: 3
World Walk (Pass Through Rock, targeting Others): 2
Pass Through Rock (targeting self): 3
Heal Body (adjacent 2BP): 3
Flame Strike (Fire of Wrath, line of Sight): 1
Fire of Wrath (no Line of Sight): 3
Ball of Flame: 2
Courage: 3
Healing Spring (Water of Healing, range 2BP): 4
Water of Healing (adjacent 2BP): 3
Sleep: 2
Veil of Mist: 2
Clairvoyance: 2
Treasure Horde (standard): 3
Find wealth (Treasure Horde, one card, Hazards have no effect): 2
Future Sight: 2
Dispel (Cancel ongoing): 1
Counter-Spell (Dispel, Cancel spell or magic trap as cast): 2
Invisibility: 2
Wall of Stone: 2
Chains of Darkness: 2
Cloak of Shadows: 3
Arrows of the Night (2 dice): 2
Soul Fire (Arrows of the Night, 4 dice): 3
And for those using my eighth “control” spell group:
Control Fiend: 3
Drain Mind: 2
Mental Fortitude (target anyone, 2MP): 2
Force of Will (Mental Fortitude, target self, 2MP, and extra cast action this turn): 3
I've not the time to develop or balence this idea, but if someone wants to run with it, I'd be happy to give pointers























