What would it take to Plane Shift, Gate or otherwise transport The Tarrasque from the Material Plane to the Elemental Plane of Water?
Look at the size limit on a Gate spell ("from 5 to 20 feet in diameter, caster's choice").
Next, look at the size of the Tarrasque ("70 feet long and 50 feet high, and it weighs about 130 tons")
I am thinking epic magic would be a viable solution.
Actually, Plane Shift has "creature touched, or up to eight willing creatures joining hands". So you could easily (well... you know what I mean) Plane Shift the Tarrasque to the Positive Energy Plane and have it die by awesome!
Hmm, interesting approach!
I actually think this would make it relatively easy to finish the tarrasque off, if done right
and given a house rule in play... Here's how I see it.
3.5 DMG said:
Major positive-dominant planes go even further.... Simply being on the plane grants fast healing 5 as an extraordinary ability. In addition, those at full hit points gain 5 additional temporary hit points per round.... However, a creature must make a DC 20 Fortitude save each round that its temporary hit points exceed its normal hit point total. Failing the saving throw results in the creature exploding in a riot of energy, killing it.
First of all, by RAW, a natural 1 is an automatic failure
only on attacks, so it will never fail this saving throw (its Fort bonus is +38). But with the very common house rule that it fails, or assuming some sort of major effect to reduce its saving throws by like -20 or something until it finally does fail, what happens?
Okay- so we've established that a lethal effect that doesn't deal damage simply increases the tarrasque's nonlethal damage total to its full normal hit points + 10. So that's what the "pop" will do to it.
Unfortunately, it's simultaneously got both fast healing 5 (from the plane itself) and regeneration 40 (from being the tarrasque). This means that its nonlethal total drops by 45 every round, and any actual damage it has drops by 5 per round as well.
So let's say that the tarrasque enters the positive energy plane with its full 858 hps. Again, assuming that nobody is messing with it- after 172 rounds, its temporary hit points are at 860 and it starts making saving throws. For the sake of argument, let's say that it fails immediately.
Now Big T has 858 hps, 860 temporary hps and has taken 868 nonlethal damage. He's not even unconscious- because those temporary hps stack right on top of his normal hit points until they go away. They're normal hit points!
3.5 PH said:
When a character gains temporary hit points, note his current hit point total. When the temporary hit points go away, such as at the end of the aid spell's duration, the character's hit points drop to his current hit point total. If the character's ht points are below his current hit point total at that time, all the temporary hit points have already been lost and the character's hit point total does not drop further.
Note again the wording of the tarrasque's "can't kill me!" regeneration:
3.5 MM said:
If the tarrasque fails a save against a spell or effect that would kill it instantly (such as those mentioned above), the spell or effect instead deals damage equal to the creature's full normal hit points +10 (or 868 hp).
This doesn't even account for the temporary hit points! So we have a supercharged, rampaging tarrasque!
HOWEVER, there is a HUGE bright side:
3.5 MM said:
The tarrasque can only be slain by raising its nonlethal damage to its full normal hit points +10 (or 868) and using a wish or miracle to keep it dead.
So you don't actually have to render it unconscious to kill it, you just need to be there when the positive energy in it "pops" and have your wish or miracle handy! But you have to time things well, since its nonlethal damage drops by 45 on its turn and never exceeds 868; when it pops, you only have until the start of its next turn to use that wish/miracle.
