OK, call me a stickler, but according to the adventure text, the cryohydra cannot, mathematically, collapse the stairs. The cryohydra deals 3d6 cold damage per attack. Given that it breathes from 7 separate heads, that means that each breath should be treated separately. Maximum damage per attack would therefore be 3x6=18 damage per attack. The text says, "Quarter the damage (because it's cold damage against an object), subtract 10 for the hardness, and apply the rest to the pegs." One-fourth of maximum damage (18) is 4.5. If you subtract 10 from that, you always get 0. Therefore, the cryohydra cannot collapse the stairs.
Naturally, I can see that you might treat all the damage as coming from a single source, since there is only one cryohydra. However, doing so seems to go against a strict interpretation of the rules. Maybe I'm thinking about this encounter in the wrong way. I plan, for example, to give each head its own turn in the initiative. Maybe that's why I'm thinking of the cold damage originating from separate sources.
When you ran (or when you plan to run) this adventure, did you collapse the stairs? Do you think the stairs' integrity is even important to the encounter's outcome? I can see how it could be -- a collapse could potentially divide the PC party, allowing the cryohydra to kill one or two PCs who have been cut off from the others. How did this scenario play out when your ran it, or, alternatively, how do you plan for it to play out?
...How did this scenario play out when your ran it, or, alternatively, how do you plan for it to play out?
The next part of the scenario (the Koa-tua city) can be quite deadly for the players. By collapsing the stairs, you cut out the only exit. On the other hand, I can easily picture an hydra combining its attacks in order to destroy a sensible target - it would dramatic - drama is good!
I think the idea of destructible stairs is more important thematically than it is in terms of the actual battle.
I've been contemplating changing the stairs from metal to stone, but making them *very* old and crumbly. The pit needs to be much deeper, also. A spiral staircase is a lot creepier when you've been going down it for several minutes. It adds suspense.
I could maybe set up the unsafe sections as traps that could be searched for, or spotted. Then some relatively easy jump checks would be in order... with a fall possibly resulting in death.
That's a dramatic introduction that sets the mood to the players: you're in danger here. Watch out.
But I don't think collapsing stairs should actually be a part of the battle. The hydra is already dangerous... at least give the party something solid to fight from.
Even if the stairs are made unusable, that doesn't mean the party is prevented from fleeing the Kuo-toas. They could at least retreat to the base of the staircase, which is MILES away from the actual shrine. And any adventuring group worth its weapons carries rope.
I thought it was open debate as to whether to consider each hydra head as a seperate attack or not. It seems I saw a debate on the WOTC boards about this...
If you consider it one attack, then you have 21d6. On average, that is 21*3.5= 73.5. Quarter that and subtract ten and you have about 8-9 points of damage every attack on average.
I didn't worry about the stair damage and I treated it like individual attacks.
Dedekind
Considering it one attack is cruel... that's an instant kill for most characters if they fail their reflex save.
Yeah, pretty much. However, treating them as individual attacks isn't much better; if you hit the same group with all seven heads, they will still take somewhere between half and full damage. If average damage is 74 and the PCs make half the saves then they would take around 55 points of damage.
Of course, what jerk would hit them with all 7 heads at once? Oh, wait, I did. And the druid died. I don't know what I was thinking at the time...
Thanks, everyone. I ran the encounter today, and the point was moot. The gnome illusionist first sent an illusory party down the stairs, provoking the hydra to move out and breathe on the illusion. Basically, the party said, "Uh-oh," and headed off to prepare spells before facing it.
A bit less than a day later, they returned, ready with protection from energy (cold), fly, improved invisibility, and also many buff spells. Three of the PCs used different spell effects to fly down, the gnome stayed at the top of the pit and cast spells from there, and the archer (actually a fighter with heavy bow specializtion) stayed up there with the gnome and shot the hydra. They didn't even touch the stairs until after the hydra was already dead!
The hydra's fast healing 17 was pretty good, but the fighter using Power Attack, the rogue under the illusionist's improved invisibility sneak attacking every round, and the archer's shooting took it down in good order, no head sundering needed. One factor that really helped the party was that I play creatures with 2 Int as though they really have 2 Int. So, it was clueless that its breath weapon was ineffective (remember protection from energy?), and never switched exclusively to melee attacks. (I even made two of the PCs roll Bluff checks because they were pretending to be hurt by the cold, but the hydra failed its Sense Motives.)
The party beat it handily.
However, that's one thing I love about my group of Players. They do things to gain intelligence, and then use that intelligence to plan highly effective tactics. Their teamwork is excellent too. The cryohydra never really stood a chance.
We'll see if they fare as well against Aushanna, the erinyes!
Aushanna has definitely been the hardest encounter for my players to date. It was the only one where they had to retreat and regroup.
Good luck with it!
However, that's one thing I love about my group of Players. They do things to gain intelligence, and then use that intelligence to plan highly effective tactics. Their teamwork is excellent too. The cryohydra never really stood a chance.
And I bet your players love that their DM rewards smart/inventive play. Bravo!
I put a lot of work into building up the hydra, and it paid off...for about two rounds. The party was split up, at various points on the stairs, with the fighter on the ground facing off solo against the beast.
Then she rolled two consecutive critical hits (she was hastened) -- with her scythe, doing x4 damage, and killing the hydra. I had no idea how to describe the result. "You decaptiate all seven heads"? It was a lovely moment.