What happens if a Troll Vinespeaker would be reduced to less than 0 hitpoints?

Question

We recently fought a Troll Vinespeaker in our DnD 4e campaign. These was some controvery over whether we could reduce the troll to less than 0 hit points to keep it from getting up the next turn, via Troll Healing:

If the troll vinespeaker is reduced to 0 hit points by an attack that does not deal acid or fire damage, it falls prone and remains at 0 hit points until the start of its next turn, when it regains 10 hit points. If an attack deals acid or fire damage to the vinespeaker while it is at 0 hit points, it is destroyed.

We mainly wanted to do this to tie up the troll until our Warlock could come over and destroy it with fire.

So, as per the rules, could we reduce the troll to negative hitpoints, or does it stop at 0?

Answer 1

There is no reason to track negative hit points for monsters in D&D4e. On a previous question I went into greater detail on the differences between monster and PC damage at 0 and lower.

From the Rules Compendium p261:

Monsters and characters controlled by the Dungeon Master usually die when their hit points drop to 0, unless an adventurer chooses to knock them unconscious.

For a PC, there is no difference between 0 and being at negative hit points. Both grant the unconscious and dying conditions.

You should be able to tie up the 0 hit point (and hence unconscious) troll. You have to knock him to 0, then bind him(use rope and a thievery check) before his turn rolls around and he regenerates. That will usually require two characters to coordinate (or a timely action point!).