Hey Blizzard.
Magtheridon is buggy since the patch, I think.
He will destroy everything, if he awaken, but he doen’t do it anymore, if you put him dormant with Maiev…
If he awaken again, he will destroy… nothing. It worked in the past, so I guess, it’s a bug. Plz fix it. Thanks. Merry Christmas u all. 
Why should he destroy the board IF he awakes from a different mechanic??? Being made dormant by Maiev literally has NO OTHER effect than “freezing” a minion on the board for 2 turns, making it immune to everything.
The “destroy everything when he awakens” is tied to the original mechanic of killing the wardens… that doesnt happen with Maiev. And I sincerely doubt that it EVER worked like that in the first place.
IF it did, than THAT WAS THE BUG
No, not really.
If you’re make a minion dormant with Maiev, like Imprisoned Antaen, he will deals 10 damage again, if the awakens.
Same with Magtheridon, but it doesn’t work anymore since the Patch.
The thing is, it SHOULDNT work like that in the first place, because the original dormant mechanic is triggered when you play the thing or when it first gets put on the board… having it pop multiple times can NOT be the intention.
Ähm… no.
That’s how Blizzard intended it. Dormant minions will trigger their awaken effect again, if you’re putting them back into dormant with Maiev. That’s NOT a bug. It’s designed by Blizzard.
According to the wiki;
The destruction effect is an on-awaken Triggered effect and is unrelated to killing Hellfire Warders. It will activate again on awakening if Magtheridon is made Dormant by another card (such as Maiev Shadowsong).
So if Magtheridon is no longer destroying all minions when he awakes from Maeiv’s effect, then that is a bug.
The Wiki is not a Blizzard source though. If that statement came from a Dev, ill be happy to accept it… 
Since it wasn’t mentioned in the patch notes, and that Mag or Maeiv doesn’t DE for full price, we’ll just assume its a bug.
Yeah IF its truly a bug caused by the patch, then Blizzard should really put in a permanent warning in their patch notes stating that “in case something isnt working as it used to, please be sure it was caused by the latest patch and will be fixed with the next patch, that will in turn break something else”
this was discussed long ago in this bug report forum when people reported the opposite as a bug, it was then concluded that it likely was an unintended behaviour that it triggered of maiev but that only blizzard knows for sure. the fact that they now has removed it indicates that it indeed was an unintended behaviour