Not a complaint at all… I never expected it to be used by a Priest on my Arcanist Dawngrasp, but I HAD to congratulate my opponent for that… Awesome counter, for the best win condition quest mage has right now… I even let my opponent C’thun my death LOL… Truly a match I did not hate losing… Well played friend 
The more you know, am i right.
Now It won’t ever work on you again
OR is it the more everyone else knows? I don’t use the card, but many other people do… OR even will… Granted, no guarantee the card will be in the deck at the right time, BUT I also know I will definitely NOT complete my quest until I can play it… SO, in a manner of speaking, indeed was a bad on my part, but again I never expected the card to be in a priest deck… I always see it in Shamen, or paladin… So yes, I guess you are right… THE MORE you know… 
Don’t forget Glide, Star Student Stelina, and that new rogue card that transforms a minion in both players’ hands into a pirate.
Yeah those too. Thankfully priest dont run those cards. Generally its better to pop last quest and play the minion the same turn vs anyone unless you know they cant mess with your hand (like mage mirror, warlock, shaman, hunter)
Very good point, and very important to remember. I almost want to add Mutanus to my handlock if only for that small, small chance of devouring their quest reward. I’ve had the opportunity once or twice, but, so far, my Mutanus ate the wrong minions.
It was a really good, smart play… That is the first time it ever happened to me… So as I said I could not be angry at all…
As others have suggested, unless you’re fighting an opponent you know doesn’t have any of these cards, try and make certain you’re able to play your quest reward minion the same turn as you complete the quest. Even if it means waiting an extra turn (unless that kills you).
I’ve caught a few people that way on my priest. They complete the quest and just don’t have the mana to play the minion…it works well against spell-heavy decks like mages to eat their reward. Feels a little dirty to do it but at this point, playing a non-aggro priest, I’ll take my wins as I can get them lol.
The card was made for a reason… I cannot consider it a dirty play… It would dumb NOT to use it if you can… Once I get dawngrasp on the board, I have very little chance to fail… Still C’thun is a concern, but they don’t always have all 4 out in time… HP might be low, but when I have ignite, it is a killer card… Almost always it wins me my game.
If I have to pick a class that would play mutanus, I would choose priest (unless they have benedictus)
I remember when people were posting that this card would be barely played. Yet It’s been used so many times… why because it’s an awesome card. 
And I love your positive vibe. 
It is really nice when players genuinely congratulating others for a match well played, regardless of the outcome.
i´be played the Deviant Supreme a fair bit for that reason, really helps in the mage matchup as most mage players are just really bad at the game unfortunately (at least d5-1). Mutanus though is still too slow, and apart from mages the only class that tends to finish quest and not play the 5drop in the same turn is Quest shaman in higher elo as it can be an awkward setup for the deck if they don´t have bloom for the finish.
Aside from the obvious “smash them in the face before they complete the quest” there are only so many counters to fast quest decks. For classes like priest that boils down to either joining the aggro throngs or trying to play control with Mutanus and Illucia and just hope you can ruin their plans. It really doesn’t work that often, and quite frankly, priest is really frustrating to play these days as I don’t enjoy the shadow/aggro style. The best way to discourage priest players is to give other classes better cards/quests/combos it seems. Yeah, I may be a bit bitter as a long-time priest player 
Mutanus is a good boi. 
He’s especially fun when you can combine him with Brann, or run him in a battlecry shaman deck.
Probably my favorite questlock counter.
Given the use of ellipses, I believe they’re being sarcastic.
If you’re playing any deck that you are not 100% sure is not running that card, you never complete your quest without the ability to play it that turn. That mutanus is just there to catch people not thinking. I bet you’ll never fall victim to that again =)
LOL if thats what you consider a counter, to QUEST Warlock, in wild, then its no wonder you were being ambiguous and refusing to post your “counters” when they were requested recently.
Got it, so all we have to do to beat questlock is play whatever crappy list you’re running that sits t10 with floating mana not even playing it lmao. Let me go grab my exodia lmao
If he’s able to counter questlock, you’re playing against a bunch of terrible players.
No decent Questlock is going to allow you to mutanus their quest reward. Anyone that does sucks.