I like the idea, but it seems too powerful, even by fan card standards. Personally, I would add to the end “Exile Mythos of Twilight Sparkle.”

@Background Pony #9A07  
Personally, I just have fun playing events with limited card pools (i.e. you have to work with just a few pacoks’ worth of cards) or playing for fun with my friends. The competitive scene is ridiculous, yes—there’s been an almost unprecedented number of card bans in the past year—but that sort of thing always rebalances itself in time.

@NachoTheBrony  
I see the MtG playerbase is not so different from Hearthstone’s after all.

A decade ago, this would be seen as totally broken.  
But then… Eldrazi. Blightsteel Collossus. Poison. Zombie Apocalypse. Don’t even remember how many shits I saw around the time of the vampire expansion. The game is irreparably broken and I got out because I felt like I needed to spend stupid amounts of money to even have fun, let alone win. “Meth for nerds” indeed.
 
Carry on.
 
But I would make this a tribal spell anyway, giving it a cost of tapping X ponies and paying X mana for X number of effects.

@FanOfMostEverything  
Better grab that Dragonlord Dramoka, else imma Fog the shizz outta that turn! lol

For those wondering, that five-Mythos turn would entail, in WUBRG order:
 
Gaining control of a tapped creature an opponent controls, exerting it, and giving it perma-vigilance. (Fluttershy)  
Casting a nonland card from your graveyard without paying its mana cost. (Rarity)  
Drawing three cards and dealing 3 damage to each opponent. (Pinkie)  
Putting a creature from your hand, graveyard, or library onto the battlefield, giving it haste, and exiling it at end of turn (Rainbow Dash)  
And finally giving all of your creatures +2/+2, trample, and double strike for the turn. (Applejack)
 
So yeah, it’d be pretty good.

This art just screamed for the extended frame; normal frames were too limited but this is to landscape to be full art. It gives a feeling like Twilight is pulling them all from their own spheres into herself, which works with the card.
 
Meanwhile, a six-mythos turn would be totally awesome.