Liches, contingency, Magic Jar and Phylacteries...

[Tyger]

Can a lich have a contingent Magic Jar spell that activates "upon the death / destruction of this body" which would then keep his "soul" in the magic jar (with all that entails), whilst the phylactery begins its creation of a new body for him??? Really, the question is more general (when does the phylactery start creation of a new body and is there a delay between the death of the lich's body and the activation of the phylactery).

If its DM fiat, that's fine - and it likely is, as most of the lich / phylactery sections in the various books are nebulous at best.

Secondly, does spell casting count as a "mental ability" for the purposes of Magic Jar, i.e. can you cast spells out of the host body while under the use of the Magic Jar spell?

[WarKitty]

I think you can cast spells, but you can't use verbal/somatic elements or material components.

[Edwin]

By RAW, probably.

Though as for the body regeneration, I think that only triggers once your soul actually enters the phylactery, and as such, won't begin until the magic jar effect ends.

But I would get a real rules lawyering type in on this.

[mostlyharmful]

Magic Jar questions are some of my favourites for breaking the game logic with, Off hand I can't see anything that'd prevent it from working however if your phylactery does build a new body I'd have some problems with you automatically bouncing back to it when the spell expires since it's not the body you started with... bit of a blue screen of death moment followed by your phylactery building another body. Easy clone I guess.

[Lord Vukodlak]

Can a lich have a contingent Magic Jar spell that activates "upon the death / destruction of this body" which would then keep his "soul" in the magic jar (with all that entails), whilst the phylactery begins its creation of a new body for him??? Really, the question is more general (when does the phylactery start creation of a new body and is there a delay between the death of the lich's body and the activation of the phylactery).

If its DM fiat, that's fine - and it likely is, as most of the lich / phylactery sections in the various books are nebulous at best.

Secondly, does spell casting count as a "mental ability" for the purposes of Magic Jar, i.e. can you cast spells out of the host body while under the use of the Magic Jar spell?

Your post is rather difficult to read but I think I get it.
Technically no while a Lich could possess a body upon his physical destruction via contingent magic jar that would probably stop the regeneration of a new body. Your phylactery is in many ways like a magic jar as it contains your soul.

Casting a spell is a mental ability if its stilled, silent and any foci or material components are already in hand. So usually no its not purely mental. And while in the jar your senses are severely limited you can't really target anyone with magic except to possess them.
Now once you take on a host then you are free to cast a spell.

[Scipio]

The rules are vague as you mentioned. I would rule that the lich is gone for all intents and purposes until 1d10 days have passed. There doesn't seem to be any indication (in the SRD at least) that the lich's soul (or lifeforce) is roaming around while waiting for another body.

My reading and understanding of Magic Jar leads me to believe the possessor can cast spells in the possessed body. Spells and SLA's should qualify as mental abilities. Unless of course the possessed body is carrying a spell component pouch, material components could be an issue. Of course if the possessed body lacks speech or a general humanoid form, it could cause problems with verbal and somatic stuff.

[Tyger]

OK, follow up question. If you are a lich, and have spell stiched (Complete Arcane) yourself, and subsequently you "die" - does the new body the phylactery makes for you have the spell stitching on it as well?

[mostlyharmful]

OK, follow up question. If you are a lich, and have spell stiched (Complete Arcane) yourself, and subsequently you "die" - does the new body the phylactery makes for you have the spell stitching on it as well?

yes. It's a template. You do it to your soul even if your soul is not currently prescent.

[strider24seven]

I believe that you retain all template that you had on your previous body, so I would say that you retain Spell Stitched.