D&D 5E Hydra and re-growing heads

[Arcshot]

Quick question about the hydra:
Players' Turn: Player 1 deals 15 slashing damage. Player 2 deals 15 fire damage. One out of five heads dies.
Hydra's Turn: Hydra attacks with 4 heads. No growing of new heads because of earlier fire damage.
Player's Turn: Player 1 deals 15 slashing damage. Player 2 deals 15 piercing damage. 2nd hydra head dies.
Hydra's Turn: Hydra attacks with 3 heads. At the end of its turn, will the hydra grow 2 or 4 new heads? Why?

 

[iserith]

Quick question about the hydra:
Players' Turn: Player 1 deals 15 slashing damage. Player 2 deals 15 fire damage. One out of five heads dies.
Hydra's Turn: Hydra attacks with 4 heads. No growing of new heads because of earlier fire damage.
Player's Turn: Player 1 deals 15 slashing damage. Player 2 deals 15 piercing damage. 2nd hydra head dies.
Hydra's Turn: Hydra attacks with 3 heads. At the end of its turn, will the hydra grow 2 or 4 new heads? Why?

The monster's trait reads:

Multiple Heads. The hydra has five heads. While it has more than one head, the hydra has advantage on saving throws against being blinded, charmed, deafened, frightened, stunned, and knocked unconscious.

Whenever the hydra takes 25 or more damage in a single turn, one of its heads dies. If all its heads die, the hydra dies.

At the end of its turn, it grows two heads for each of its heads that died since its last turn, unless it has taken fire damage since its last turn. The hydra regains 10 hit points for each head regrown in this way.

So the answer is two heads. One head has died and it hasn't taken fire damage since its last turn. If the PCs instead lopped off two heads before the hydra's turn and didn't inflict fire damage, then we'd see 4 heads generated.

 

[Arcshot]

This makes me realize that, based on my (flawed) example, the hydra should not even lose any heads because the hydra did not suffer more than 25 damage in a single turn. Each player's turn causes only 15 damage.

So the amended example should be:

Player1's Turn: Player 1 deals 25 slashing damage. One out of five heads dies.
Player2's Turn: Player2 deals 15 fire damage.
Hydra's Turn: Hydra attacks with 4 heads. No growing of new heads because of earlier fire damage.
Player1's Turn: Player 1 deals 25 slashing damage. 2nd hydra head dies.
Player2's Turn: Player2 deals 10 piercing damage.
Hydra's Turn: Hydra attacks with 3 heads. At the end of its turn, will the hydra grow 2 or 4 new heads?

 

[iserith]

This makes me realize that, based on my (flawed) example, the hydra should not even lose any heads because the hydra did not suffer more than 25 damage in a single turn. Each player's turn causes only 15 damage.

So the amended example should be:

Player1's Turn: Player 1 deals 25 slashing damage. One out of five heads dies.
Player2's Turn: Player2 deals 15 fire damage.
Hydra's Turn: Hydra attacks with 4 heads. No growing of new heads because of earlier fire damage.
Player1's Turn: Player 1 deals 25 slashing damage. 2nd hydra head dies.
Player2's Turn: Player2 deals 10 piercing damage.
Hydra's Turn: Hydra attacks with 3 heads. At the end of its turn, will the hydra grow 2 or 4 new heads?

Right or wrong, I've never run it that way. When it takes 25 damage cumulatively before its next turn, I have it lose a head. This would naturally make it easier in terms of difficulty, but I never felt that the way I ran it was easy on the players. The last time I put one in front of the party, it was in a lake, the PCs were on a muddy shoreline (difficult terrain, potential for sinking), and the area had clouds of explosive swamp gas floating about which also obscured the sun (dim light).

 

[CapnZapp]

This makes me realize that, based on my (flawed) example, the hydra should not even lose any heads because the hydra did not suffer more than 25 damage in a single turn. Each player's turn causes only 15 damage.

So the amended example should be:

Player1's Turn: Player 1 deals 25 slashing damage. One out of five heads dies.
Player2's Turn: Player2 deals 15 fire damage.
Hydra's Turn: Hydra attacks with 4 heads. No growing of new heads because of earlier fire damage.
Player1's Turn: Player 1 deals 25 slashing damage. 2nd hydra head dies.
Player2's Turn: Player2 deals 10 piercing damage.
Hydra's Turn: Hydra attacks with 3 heads. At the end of its turn, will the hydra grow 2 or 4 new heads?

While you noticed the second time the phrase "since its last turn" appeared, you missed the first one:

"At the end of its turn, it grows two heads for each of its heads
that died since its last turn, unless it has taken fire damage
since its last turn."

Answer: it will grow 2 new heads for the single head lost in round #2. It can't replace heads lost earlier (at least not using combat statistics).

 

[Kobold Stew]

Fire cauterizes any decapitating wound, preventing regrowth. (and so the answer is 2).

I like to think by the time players encounter a hydra, there are a dozen stumps there already from previous encounters.

 

[CapnZapp]

Fire cauterizes any decapitating wound, preventing regrowth. (and so the answer is 2).

While you're generally correct "the first head doesn't sprout new ones" your reasoning is off:

The reason new heads doesn't grow isn't because the hydra took fire damage. The reason is the head wasn't cut off in the last round.

Currently, the only standard way that a stump can be prevented from growing new heads is because the decapitation was cauterized, but if there are non-standard circumstances that makes a DM rule no new heads sprout, the difference becomes important.

The important bit relevant to the OP's question is this. The stat block language is clear in that the grow-back feature only applies to heads that died since its last turn.

Cheers!

 

[dinsdale]

Or you can just keep cutting heads off until the hydra passes out

http://www.giantitp.com/comics/oots0325.html
http://www.giantitp.com/comics/oots0326.html