Quote Originally Posted by Trickster View Post
I was indeed looking for all spells known, so far my optimal head cannon would be: Theurgy Wizard (I'm not quite banking on it but my DM's cool about it) a dragon mark (how do those work? Can I be a dragon marked variant human and still have an extra feat?) which dragon mark? Now I have maybe 2-3 levels to work with... Cleric with a different domain? Or just straight wiz 20?
if you want to maximize the number of spells you can cast at a moments notice then you're looking at a weird hodge-podge where you multiclass into basically all the full caster classes. at least 1 level in each would technically max. thats because the first level in a casting class gives the most bang for you buck...or rather, the most spells available/level.

for example: the first level of wizard gives you 1+int mod spells you can prepare. say 3 and int of 14. every level after that only adds 1 per level except for the levels that you get an ASI, which give 2. both druid and cleric are similar. then spontaneous casters each have their own numbers. 2 for sorcerer and warlock and 4 for bard.

cleric levels give an average of 2 spells per level up to level 9 because of their domain spells. and land druids almost match that because they too get domain spells.

but the reason you still would want to multiclass is not just the leveled spells, but also the cantrips. when you add in cantrips, you can't match taking 1 level in each full caster class for most numbers of spells available at any given moment.

basically what i think this would look like is sorc/lock/bard/wizard 1, cleric 9, druid 7, to *actually* maximize spells. but a far less ugly, while also less optimal, way to do it would be to pick 5 caster classes that you take 4 levels each in. that way you get your ASI's at the levels you're meant to, rather than at weird times.