I'm on board with all the ideas proposed.
This could also open the gates for some true Wild Magic spells, like the old Nahal's Reckless Dwemer that automatically triggers a wild surge but allows you to roll more favorably.
The only concern I have is too many tables or too many nestings: one main...
Well, there's one creature as a target, and up to three additional. You could cast this spell against a single target of course, so even a very strict DM should allow to use the spell and disallow the secondary targets (albeit this would violate the spell's description). One could do even worse...
I was playing a bit with the Bladechanter synergy feat, eligible spells, and the final feat of the chain (Eldritch Whirlwind Master) that allows to target as many enemies as the spell level cast as a reaction (within 10 feet).
Then I found out that Chain Lightning is cast as 1 action and has 1...
Also, the bladechanter feat that allows to cast a spell with a reaction also specifies that the spell must be 1st level or higher and both Booming Blade or Green Flame Blade are cantrips
Communications: ...The space slug name is Abbot, and has a friend named Costello. They find it easiear to communicate with us with these strange smoky symbols... Now I have a deja-vu
One thing I'm noticing, besides the weird interactions with staff and warrior monk, is how it specifies that you must not have disadvantage on the attack.
What if someone has advantage on the attack instead?
On one side the attack has advantage, the player decides to power-attack, getting +10...
Not sure if this is already a thing in LU, but 2e at a certain point had a "Universal" school that contained some spells available to everyone able to cast spells.
This one might fit snugly into such a classification IMO
I really love this fourth draft! It seems to have a lot of reasonable checks and balances while still being very flexible!
A wizard capable of 5th level spells can grant perma-flight to all the party for the reasonable cost of 1 attunement slot each (and some money)
Or himself can be...
A gleefully evil way of using this would be to not only apply permanent curses and debuffs on a target, but also severing their attunement to their own magic items!