After looking a bit further, I realised that they did already address this here, so I suppose I have my answer - https://plarium.com/forum/en/raid-shadow-legends/843_news/42540_raid-digest--03-11-23/

[Taunt] buff vs. Hydra

Some players wonder if it is normal that the [Taunt] buff prevents Hydra from devouring Champions. Yes, it is a viable strategy: when a Champion in the player's team is under [Taunt] buff, Hydra cannot target anyone, apart from the taunting Champion. If that Сhampion under [Taunt] doesn't have a devouring mark, then the devouring won't happen until the buff is gone. So if the devouring mark is on somebody else they are relatively safe from the Hydra's embrace.

On a side note: we keep monitoring individual Champions' performance on Hydra to make sure there is no single Champion who grants too much of an advantage in this content.  

So, may as well use this thread to plan out my team. Can't use Emic unfortunately, since his gear is optimized for FK H10, and therefore he hits like a wet noodle. No Acrizia. I'd think my choices are thus:

• Artak
• Royal Guard
• Husk
• Geomancer

If there's any other obvious candidates I should be considering, let me know. If not, which of those four do you think will do the job best? My gut feeling is either Geomancer, seeing as how he's going to be getting boosted constantly, I'd expect he'll be able to place that debuff on everyone, or Royal Guard for just pure face damage + the speed down. In place of Siphi, I'd probably be running Elva, for a backup reviver just in case - though Brogni is also an option.

Precisely. Taunt preventing Devour is as intended. Of course this can break down when your Taunt champ has the Devour debuff, as they will still get eaten lol

Any thoughts on the next question I had, regarding which champ to put in the DPS slot?

Ah. After digging into this team more, I think unfortunately I can't sub Ruarc in for Emic. Didn't realise the team was built around the three CD decreases from the two Emics + PK, ontop of the double unkillable from the Emics. Sadface.

Does look like there's another one built around double PK + Emic + Maneater though. Might try that one out instead. 

No Acrizia?  I thought you had every champ in the game.  

Alright. So, been doing some mulling, and I'm thinking this team should work:

• Emic (fastest) - 6 piece protection set. 9 ideally, but I doubt I have the pieces for it. Goal is to have as good a chance as possible of making the Taunt buff be protected. 450+ RES, so there's only a 3% chance of it being stolen, but I still need to minimize it as much as I can.
• Pain Keeper 1
• Pain Keeper 2
• Elva - SPD up, block debuffs, and backup RES
• Shamael
• DPS - same question as earlier.

Thoughts? Taunt will be perma-active, and unkillable will be active for most of the fight too, just as a safety precaution, along with Emic's shield.