warlock multiclass spell slots
Do the involved classes share the same pool of spell slots?
Dungeons & Dragons: Multiclass Spell Slots, Explained. ... All multiclass spellcasters use this table to determine the spell slots that they have available.
Baldur's Gate 3: Shadow Magic Sorcerer's Hound is Great for One ...
Assuming multiclass with Paladin 3/Sorcerer 10/Warlock 7, he will have 11 levels of spell you have 16 slots now. One being level 6 which is not otherwise available to Paladins.
More Spell Slots - Baldur's Gate 3
If you do multiclass, please see this chart which details how your spell slots would work.