ToME: the Tales of Maj'Eyal

It's my first time in Dreadfell. My lvl 24 necromancer (sorry I come from an ADOM background where all characters are playable from the get-go) is a lot of fun, and me and minions were dominating until a lvl 40 phoenix showed up. It took me to the very brink of death before I killed it. Then it appeared again. I managed to teleport away, heal up again, summon my minions, and had another epic battle. And it appeared again. Yes I know a phoenix is born again and again from its own ashes. But is there a way to permanently put it down, or am I going to have to deal with it and the Master at once?

You have to damage the egg to kill it.

You don't however, have to kill it.