I believe it. I don't really play as Mage much but I play against them of course and you can play around their burn deck somewhat but if you do... and they aren't running burn....you fall on your face.
I think this is one reason mages are bullshit in arena, you never know how to play against them. Play too careful, get nuked down. Play too fast get flame striked. In constructed you probably know what the aim of their deck is by turn 3. In arena all you can really do is try to play against flamestrike which can easily bite you in the ass. Playing safe makes it easy for them to ignore your shit and go for face + nukes. Playing big creatures makes you weak vs polly, fireball, and freeze. Basically are are forced to slightly overextend and hope for the best. I have to wonder if easy access to Truesilver Champion and Guardian of Kings is the sole reason why Paladins are so successful in arena just because those two cards are great answers to flamestrike, fireball, and freeze.
And then theres always the mage with a crazy deck once you get past 6 or 7 wins. Heres a good one from last night:
He has a water element out and something else. Sheeps one and trades with another, leaving him with a water elemental and a clear board.
I play either a sin'jin or yeti, cant remember which. Fireballed
I play a 6/7 orge, he plays cone of cold, wtf?
I play war golem, he plays another cone, wow really?
I play another war golem, haha fuck you flamestrike! He plays blizzard
I just play some crap 2 drop in case this asshole has flamestrike. Nope, its another blizzard, are you fucking kidding me.
I play 2 random mid range drops, cause theres no way he has flamestrike in hand, right....right? Wrong again Bob, its a flamestrike!
I drop everything I can cause I'm getting low from this goddamn water element thats still alive and some crap 2 drop + pings. He plays....ANOTHER FLAMESTRIKE! But wait, by some miracle I still have a creature alive! Nope, better throw a frostbolt at it.
I dont have much left at this point and he doesn't need a whole lot for lethal next turn. Fireball to the face, dead. I'm just in shock at this point, laughing maniacally.
15ish cards in he had: 2 or 3 frostbolts, 2 fireballs, 2 cones, 2 blizzards, 2 flamestrikes, 1 sheep. You cant win vs that, hell your not really even playing the game.
Here was another fun one:
Mana wurm
arcane missiles, mirror image
frost bolt, coin, 2 drop
cone of cold
frost bolt + ice lance to the face
fireball face
At least half my arena losses are from mages, and probably 65-75% of my losses past 6 wins. I even go out of my way to draft against mages specifically, making me weak vs other classes. Fuckina I'm salty =/