Damage at 0 hp / Massive damage clarification?

Quickleaf · Sep 29, 2018

If a monster – with a Multiattack (x2) dealing 6d12+4 damage with each attack – hits a PC/NPC with hit points equal to or less than that number, reducing the PC to 0 hit points, and then hits with its second attack...how is that second attack within its Multiattack resolved?

Do I use the Instant Death rule or do I use the Damage at 0 Hit Points rule?

Instant Death:

PHB 197 said:
Massive damage can kill you instantly. When damage reduces you to 0 hit points and there is damage remaining, you die if the remaining damage equals or exceeds your hit point maximum.

Damage at 0 Hit Points

PHB 197 said:
If you take any damage while you have 0 hit points, you suffer a death saving throw failure. If the damage is from a critical hit, you suffer two failures instead. If the damage equals or exceeds your hit point maximum, you suffer instant death.

Thanks!

Ristamar · Sep 29, 2018

Damage at 0 hit points. It's essentially the same rule with additional consequences for being at 0 hit points when taking damage. The effects are resolved for each instance of damage.

guachi · Sep 29, 2018

The latter. If you already at 0 HP the first rules won't apply. It's one of the rare nasty effects that can actually lead to death in 5e.

robus · Sep 29, 2018

there are two very different situations. the first is catastrophic damage, where the total remaining after taking you to 0 HP equals your HP maximum. The second is if you’re hit while at 0 hp.

So your multi attack fits into the second case: the first attack takes you to 0, the second attack takes a death save, or two if it’s critical.

leogobsin · Sep 29, 2018

The second. The first only refers to taking damage that takes you to 0 and has remaining damage all from one source. The multiattack is two different sources of damage: the first takes the character down to 0 (and kills them if there's remaining damage greater than or equal to their max HP), the second causes a failed death save (and kills them if the damage is equal to or greater than their max HP).

Slit518 · Sep 29, 2018

Either, both result in instant death.

77IM · Sep 29, 2018

Roll damage, and if the total is greater than the character's hit points, the character dies. If the roll is less that the total hit points and not a critical hit, it's 1 death save failure; if it was a critical hit, it's 2 death save failures. Either way, not great news for that character.

S'mon · Sep 29, 2018

Does the second attack get advantage and be an automatic critical, since the target was already at 0 hp & helpless when it was rolled? AFAICT that's the RAW.

leogobsin · Sep 29, 2018

S'mon said:
Does the second attack get advantage and be an automatic critical, since the target was already at 0 hp & helpless when it was rolled? AFAICT that's the RAW.

It would always have advantage, and would be a critical if the attacker is within 5 feet.