BG3: Respec, Revive, and Replace!
Act 1:
Withers is a "friendly" Lich you can find within the ruins in the game Baldur's Gate 3. This guide shows where the ruins are and why this NPC is important.
They let your revive your fallen allies, respec your classes(within reason, no Oathbreakers allowed), and replace any empty party slots with hirelings!
To unlock hirelings, simply get any class to level 3 and then talk to Withers at camp.