@@kohaiame2691 The quest board in Cassardis (the beginning village place that you start off in at the beginning of the game) and is in the inn named "Pablos' Inn", the quest is called "A Challenge", the hydra is in the frontier caverns which is where the shadow fort is.
There was an arch hydra in the Everfall segment I remember. I figured it was a really really bad idea to fight him because all my pawns were pretty much dead. And they all "did" die too immediately. lol Then I tried to solo it as my level 63 ranger self only to get blinded and eaten shortly after. Watching the lump slowly move down its throat till you die sucked. When I respawned I just left and fell down the hole to the next room. I didn't look back. lol
For some reason, during this fight my pawns just act like complete morons. You need fire to scorch the wounds, but my sorcerer pawn didn't use fire spells (and refuses to complete the casting most of the time), The mage pawn didn't use fire affinity on me and the warrior kept swimming in the poison. Took me at least an hour to kill him as a ranger.
If you're using Daggers, with Double Vault and Forward roll it's really easy to climb one head, lob it off, jump to the next, chop that off, and keep going. Hydra's surprisingly easy to solo as Strider/Ranger
pawns fight better when they have knowledge on the enemy the pawn you were may not have had knowledge on Hydras also it could be that the pawn had bad inclination which a lot of pawns in Dragon's Dogma do
Never play hardmode of this game, the times I tried to climb the Arch Hydra only to get instant killed by pretty much every attack cost me a few retries and some sanity.
Hydras are pretty nice fights. But I have to ask, what was unique about the archhydra compared to the normal one? It just seemed like a small damage boost.
From my experiences, the differences are: - As you said, arch is stronger and has more defense. - Different elemental weakness, you can use holy against regular hydra, but arch just brushes it off. - Arch can swallow the arisen and pawns much quicker compared to regular hydra. - It's harder to struggle against the devour attack form an archhydra That's about it I guess.