Dvati Deific/Non-Deific Duo

[Rubik]

Okay, yet another dvati oddity.

Let's say you've got a high level dvati psion. One uses Fusion and Astral Seed on a deity, gaining a divine rank in the process.

What happens to the other one? Does it stay mortal?

[Doc_Maynot]

A dvati is a singular being, they just are one with two bodies. They would gain the divine rank.

[The Oni]

What about one dvati body being prepared for lichdom? Transitioning directly from life to undeath isn't technically death, so would the other twin die? Or would it remain alive while only its soul is that of an undead creature?

[Doc_Maynot]

Since "Undead are once-living creatures animated by spiritual or supernatural forces." (http://www.d20srd.org/srd/typesSubtypes.htm#undeadType), that would probably fall under:
"If one dvati twin dies, the other slowly sickens and perishes. Each day that passes after a dvati twin dies, the surviving twin takes 1d4 points of Constitution and Wisdom damage and takes a cumulative -1 penalty on attack rolls, skill checks, and saving throws. The ability damage and penalties remain (and cannot be healed or removed) until the living twin dies or his soulmate returns to life (at which time they immediately disappear)."