After this update,  taunt won't help anymore unfortunately.  Currently the taunt buff stops devours completely unless taunt champion is the target of the debuff. 

I understand that Taunt will no longer prevent the devour from occurring. The update says "If a champion has the taunt buff, the Mark of the Hydra can only be placed on that champion". This means that the first Mark of the Hydra will go on your champion with the highest Crit Damage, then if you have taunt up when that champion is devoured, the next Mark of the Hydra will go on the Taunt champion. Then when the taunt champion is devoured the next Mark of the Hydra will go on the champion with the highest crit damage. I want to know if that will be the same champion as the initial Mark of the Hydra, or if it will be the champion with the second highest Crit Damage. Basically I'm trying to find out if the Taunt champion being devoured resets the target list, or if it continues as usual other than the Taunt champion jumping in line when they have taunt up when another champion is devoured.

It doesn't redirect to taunt currently, my endless taunt team had a few gaps and taunt just wandered through the team a bit, but it did delay the devours enough to keep it manageable. 

I think the issue is that currently if someone has taunt up then the other Mark of the Hydra target can't be consumed devoured, so for a Mark of the Hydra target to be consumed devoured by definition taunt can not be up, which means the next Mark of the Hydra isn't going to be redirected to the champ with taunt up, because there can't be a champion with taunt up. That's why I'm wondering what happens after this change. If I had to guess, I'd say Plarium hasn't thought about it and they might not even know what will happen. 

In any case, the devours are going to be a much bigger problem with the shorter decapitated head timing and the 100% damage reduction from Serpents Will.