Handling killing Fast Regen monsters and less than 0 H.P.

[Gwiber]

Fought a Mythic Troll today, and I must say, what a F*cking beast.

At any rate. I managed to drop the thing into the negatives, and still had one arrow of damage to roll, when the DM wanted to stop me from rolling damage.

My contention was that I should keep rolling damage to determine how far into the negatives the Troll was being taken, so when he started to regen H.P. he would still have to work through the negatives to get back up.

The DM wanted to stop right there, at whatever negative he was at from the last hit that dropped him into the negatives.

Which of us was right?

The DM eventually took it my way, but did I make the wrong call?

Note: By that point in combat, the thing was regen'ing 25 H.P. a round.

[Secret Wizard]

Why would you ever stop attacking? The thing wasn't dead, it was just unconscious.

[Gwiber]

I, didn't. But my DM wanted me to stop rolling damage once it went under 0HP and went down.

He seemed to feel that once under 0 H.P.; damage should stop.

My contention was KNOWING the thing was regenerating, that I should continue heaping damage on it forcing it into deeper negatives to prevent it from standing up, while one of my party got a torch lit to burn the thing out.

For whatever reason the DM was of the opinion once under ) H.P. and down, more attacks wouldn't have counted towards damage for more negatives in H.P.

IN the end he did agree with me about being able to inflict more damage to push the negatives further, but I can tell he didn't seem like he agreed too much with that.

I'm just trying to find out if there is a rule I can point to, to convince him fully.

[Under A Bleeding Sun]

You were right, he was wrong

[Paladin of Baha-who?]

There would need to be a specific rule that says you stop counting damage below 0 hp. There isn't, so you apply normal math. Incidentally, if you stop counting damage below 0 HP, that would mean that no living creature would ever die from HP damage, because living things die at a negative amount of HP equal to their Constitution score, not at 0.

[Ipslore the Red]

When a creature dies, it becomes an object. An object has a fixed number of HP and is destroyed at 0. Therefore, normally you can damage a creature to negative Con, then destroy the corpse.

Against a creature with regeneration, you can damage it forever since it does not die at negative Con unless a specific material or damage type is used.

[boring7]

The "logic" the DM was using is (I presume) thus: Once you chop someone's head off, cutting slices off of the neck-stump doesn't do much.

The DM was wrong, of course.

Other thoughts of tangential relevance: Technically the troll was just unconscious at 0 HP, and would have to drop to -23 to be semi-dead.