Vampiric Feast and it's effect on the lifespan

[Korchas]

Pretty much the question in the thread name, honestly.
It is a question that came up during a casual chat ingame, IC as well as OOC, whether the epic spell vampiric feast, given that it directly harvests the life force of whatever you drain with it, would not end up invigorating or rejuvenating you or, at the very least, extending your lifespan, similar to other epic spells in lore (i.e Iolaums longevity)?
I could not come up with a definite answer myself, as points can be made for all the options, although my personal headcanon (and my characters potentially faulty opinion) went into it shoving you in the direction of your prime age physically and extending your lifespan, although there is no indication as to "how long" that would be.
Since my character can actually cast the spell, and it was a reason for another to learn it from her if it had even the slightest chance of prolonging her existence, it would be rather prudent to actually know for certain if it comes up again.

[DM Arkanis]

Pretty much the question in the thread name, honestly.
It is a question that came up during a casual chat ingame, IC as well as OOC, whether the epic spell vampiric feast, given that it directly harvests the life force of whatever you drain with it, would not end up invigorating or rejuvenating you or, at the very least, extending your lifespan, similar to other epic spells in lore (i.e Iolaums longevity)?
I could not come up with a definite answer myself, as points can be made for all the options, although my personal headcanon (and my characters potentially faulty opinion) went into it shoving you in the direction of your prime age physically and extending your lifespan, although there is no indication as to "how long" that would be.
Since my character can actually cast the spell, and it was a reason for another to learn it from her if it had even the slightest chance of prolonging her existence, it would be rather prudent to actually know for certain if it comes up again.

I'll quote you what it says from the, "Mask of the Betrayer" book that comes with the CD version of the game concerning Vampiric Feast:

"When this spell is cast, you drink in the life force of enemies in the area of effect. Creatures who succeed at a Fortitude save (DC+5) lose only half their remaining hit points, while those who fail their saving throw lose all their remaining hit points and are instantly slain. The total amount of damage done by this spell is then added to the caster's hit point total. Moreover, the life-force of slain creatures coalesces as a Greater shadow, which will attack any surviving enemies. Very powerful creatures are unaffected by this spell.
You are only able to absorb sufficient hit points to return you to full health. Any remaining life force dissipates into the fabric of the Weave."

So the caster should regenerate hit points up to full based on this language, but any additional benefits that could be gained from the life force draining of others is used to create a Greater Shadow, or is dissipated into the Weave. It appears that the game creators did not include any sort of verbiage with respect to extending the castors life, perhaps because NWN2 doesn't really take age into consideration for game mechanics (if you character were to die of old age it would be done through RP) or because there are other spells that perform this function.

In my opinion, you could make an RP case that a character who casts Vampiric Feast and regains hit points is actually extending her life by doing so, i.e. she will live longer because she has the ability to cast this spell. I don't think there is an in-game way of proving or enforcing this though outside of DM approved RP.

Ark

[DM Soulcatcher]

^I basically agree with Arkanis there. 'cept one thing. When a spell restores you to your full Hit Points and rest of the life energy is dissapated into the Weave, that should tell you directly that the spell does not actually prolong your life in any real way. It's kind of like Vampiric Touch, but instead of adding you temporary hit points, it heals all your wounds.

In Forgotten Realms there are spells that when they extend life, they specifically tell you to do so. One of such spells you can find in Waterdeep: The City of Splendors

ENSUL’S SOULTHEFT
Necromancy [Evil]
Level: Sorcerer/wizard 9
Components: V, S, M
Casting Time: 1 full round
Range: Touch
Target: Living, corporeal creature touched
Duration: 1 round/level (D); see text
Saving Throw: Will negates
Spell Resistance: Yes
Crackling black radiance surrounds your left hand. While the spell lasts, you can make touch attacks to steal the lifeforce of another creature in a manner that heals and renews you, diluting diseases and poisons, and prolonging your life span. With a successful melee touch attack, you drain 1d4 points of Intelligence from the victim touched. This is permanent ability drain. For every point of Intelligence drained, you heal 5 points of damage. Healing in excess of your normal maximum is retained as temporary hit points that fade after 1 hour. In addition, you receive an immediate Fortitude save against any diseases or poisons currently ravaging your body when you drain a foe’s Intellligence, as long as the disease or poison in question allowed a Fortitude save in the fi rst place. The DC for this saving throw is the same as the DC of the original effect that poisoned or infected you, and there is no penalty if you fail this new saving throw.
If a victim is reduced to 0 Intelligence as a result of this spell, it dies. A victim slain in this manner is forever dead and cannot be brought back by raise dead, resurrection, or similar magic unless used in conjunction with a miracle or wish. When you slay a victim in this manner, you do not age for a number of days equal to the number of points of Intelligence drained. If the victim was a spellcaster, the gain in lifespan is increased by the sum of the spell levels prepared by or available to the victim at the time of death. If the victim was a psion, the gain in lifespan is increased by a number of days equal to the victim’s power point reserve.
Ensul’s soultheft lasts for 1 round per level, during which time you can attempt touch attacks as often as once per round. Some users of this spell arrange for the victim to be restrained or otherwise helpless, so that they can be easily drained for multiple rounds.
Material Component: A drop of blood taken from a vampire.

[Korchas]

So the basic spell, as it is, would likely not affect the lifespan, at the very least not in any notable way.
Could one try to alter it in a way so that the excess lifeforce does not in fact dissipate or coalesce into the shadow, but be used in some measure to prolong your life? Even if not the impressive one-year-per-victim of Ioulaums Longevity?
With DM involvement and an appropriately long time of research, of course?

[DM Arkanis]

Send the DM team a PM and give us as much detail as you can on what you'd like to do, and we'll get back to you.

Ark