This is a variation on neostorm inspired by me getting to do this on the FNM Omnipotence mode of Arena. I can't build this in real (virtual) life so here we go!
The key combo here is Dualcaster Mage
+
Mythos of Illuna
, which allows you to generate infinite copies of Dualcaster Mage by casting Mythos (any target is fine), casting Dualcaster Mage, targeting Mythos with the Dualcaster copy ability, and targeting each new copy onto Dualcaster Mage, thus generating a new token copy of Dualcaster mage, which then adds to the stack another copy of the Mythos, duplicating Dualcaster, which duplicates the Mythos, at which point your opponent likely quits or otherwise laughs in Settle the Wreckage.
Assuming you manage to generate an infinite number (or lethal number) of Dualcasters, there are a few ways to win. One way is a haste enabler (Ogre Battledriver/Tuktuk Rubblefort), and the other is a creature which deals damage on entry (Ral/Terror of the Peaks). Terror is hard to get down, as seven mana is kind of hard to get to, hence Irencrag Feat, but this does come at the cost of delaying the combo.
Why this and not Neostorm? Because I'm cool and different, that's why. Really, though, this has a few distinctions, which may not make this better per say, but certainly different. First of all, this is a two-color deck, which with the pathways, check lands, and shock lands makes the mana base a little better (not a great advantage, but not a bad one either). Second, you really only need to have one piece at a time for the combo to work. Mythos can target a Dualcaster that's already out on the board, meaning all you need is four mana to win (admittedly, two turns further than neostorm). Finally, this deck can win on the turn the combo triggers, which means you don't need to worry about a wipe, and it can also do this combo at least three more times should you get wiped.
