Malygos and Sapphiron under investigation!

[Fenz]

Sapphiron - Aura bugged / not affected by Frost resist?
We've made no explicit changes to the encounter on the design side to change how the frost aura works. When Sapphiron enters combat, he casts a spell on himself that every 2 seconds casts the debuff players receive, which you see as "Frost Aura". That debuff is a 5 second duration damage over time effect that deals frost damage every second. The only difference between the 10 and 25 player versions of these spells is the amount of damage.

So if you were only getting damaged every 2 seconds previously in a 10 player raid, and still are only getting damaged every 2 seconds in a 25 player raid, there's some kind of odd bug going on that I'll have to track down. Especially since the data says you should be taking damage every second.

Once we find out what he bug is and correct the problem, we'll adjust the numbers if needed to closely match the damage that players have been experiencing when WotLK shipped. We're not trying to adjust the difficulty of this fight, but we need to determine what's happening so this bug doesn't cause problems with future encounters.

Sapphiron - not casting all the Ice Blocks he should
We're also trying to track down why Sapphiron decides to occasionally not cast all the Ice Blocks he should.

Malygos - bugs in 3.0.8
We're checking into the various issues noted here, including why his cone breath hits targets behind his centerpoint, issues with malygos deciding to attack in phase 2, and trying to make the defense bubble's protection work even if you enter the bubble in between the time a missile is launched and when it lands.

Malygos - Feign Death not working is "intended"
Feign death not working in actually intentional, but certainly not desired. It was causing a very nasty problem, and we've been trying to figure out a way to handle the particular boundary case without setting the creature flag that ignores feign death.