That would actually make for a really great NPC. Rescue an old man’s severed head kept alive for decades in an evil wizard’s basement using the Wizard’s own stuff, then Gandalf the Schwarzenegger’s jacked body picks up a sword and wins initiative on the BBEG upstairs.
Optionally make the BBEG really tough without him there so the party is forced to figure it out, unless you don’t like railroading.
That would actually make for a really great NPC. Rescue an old man’s severed head kept alive for decades in an evil wizard’s basement using the Wizard’s own stuff, then Gandalf the Schwarzenegger’s jacked body picks up a sword and wins initiative on the BBEG upstairs.
Optionally make the BBEG really tough without him there so the party is forced to figure it out, unless you don’t like railroading.