pallandrome
First Post
Honestly, if they see it coming, even a round in advance, and know how to deal with it, it'll be a cinch. The trick is to use the fighter as defensively as possible to slow down the Hydra while the rest of the party piles on with the ranged attack. The AC20 meleer becomes an AC24 (or more) meleer, and the rest of the team will roll over that 15 fast healing a lot quicker than you might have imagined. The hydra, with a +6 attack bonus will only hit the fighter on a 19 or 20. If the other players can boost the meatshield AC be even a SINGLE POINT, then the monster has to roll a 20. It'll be a tough fight, sure, but is about right to challenge the party.
On the other hand...
You have already stated that the situation they are going into gives the hydra a distinct advantage. Whenever calculating CRs, it is generally a good idea to beef up a CR if the situation favors the monster considerably in any way. For example, I would hesitate to throw a CR4 Huge Shark against a group of level 6s if they just got tossed out of a boat.
On the other hand...
You have already stated that the situation they are going into gives the hydra a distinct advantage. Whenever calculating CRs, it is generally a good idea to beef up a CR if the situation favors the monster considerably in any way. For example, I would hesitate to throw a CR4 Huge Shark against a group of level 6s if they just got tossed out of a boat.
