(2/3) Appeal: Primarily a Txmmy/Jxnny card (something something Mirror Gallery/Rite of Replication). Yes, for Spike it's a beater that self-protects, but it's a bit expensive to be "just" that for Spike's tastes.
(2.5/3) Elegance: A card concept like this is always going to be a bit complicated but I think you get the point across well enough.
(3/3) Viability: Colors are right (red gets haste and power pump, blue gets small creature flying and shares blink with white), feels very Izzet, and this does seem like a bizarre enough card to be mythic.
(3/3) Balance: On its own it's a fair evasive, self-pumping and blinking creature. As a combo card it seems expensive and relatively difficult to make go infinite, so there you have it.
(2.5/3) Uniqueness: Ultimately has a firebreathing variant... but a really strange, new, and cool firebreathing variant.
(2.5/3) Flavor: Really neat name; lots of text there so I guess there wasn't a lot of room but short flavor text would have been ideal.
(3/3) Quality: Seems fine.
(2/2) *Main Challenge: Since apparently blocking Emrakul counts, this passes.
(1/2) Subchallenges: No white or black, but an "end".
(2.5/3) Appeal: Txmmy does like the amusing experience of making opponents' creatures Sheep even though the effect isn't all that splashy. Jxnny has ways to abuse the activated and triggered ability both and Spike loves the efficiency and utility.
(2.5/3) Elegance: A bit text-heavy (and line break-heavy) but not inelegant.
(2.5/3) Viability: I will say this card is considerably more blue than it is green. It could safely be monoblue, in fact, or at least should maybe have had a weighted cost like 1GUU. However, I would definitely prefer this to be a mythic for Limited.
(2.5/3) Balance: A very very very strong card in a vacuum, but not, in my estimation, broken. A fairly scary commander, though.
(1.5/3) Uniqueness: This card wears its influence on its sleeve. However, it's enough of a twist to make it a quite interesting throwback/mashup card.
(2.5/3) Flavor: "Baahon" is a bit too cute/too Un- for a black-bordered card name, although the ovinomancy discipline has silly flavor but deadly serious mechanics, so it seems.
(2/3) Quality: Wrong mana symbol order. For correct usage of "its" versus "it's", see here.
(2/2) *Main Challenge: Good.
(2/2) Subchallenges: Done.
(0.5/3) Appeal: Who does a core set common appeal to outside of Limited? Spike for a cheap sideboard answer, maybe?
(3/3) Elegance: Full points here, this effect is extremely simple.
(3/3) Viability: Can't argue with such an old, retreaded effect.
(2.75/3) Balance: One-mana unconditional creature destruction has something sketchy about it even though I think green could get this and it probably would usually not be too offensive. However, if many of the best creatures in a Standard happened to be flyers, green would have the single best and cheapest removal piece, which is just wrong imho.
(0/3) Uniqueness: Can't give you anything for Wing Snare but cheaper.
(1.5/3) Flavor: This card's flavor is extremely generic - which is fine most of the time for what this card would be, which is a Core common, but for the MCC I prefer to see more original flavor. The flavor text does add a bit of local interest at least with the Lorwyn references.
(2.25/3) Quality: "Faerie," not "fearie," and the last sentence of the flavor text is a bit ungrammatical as well - I know conversational speech doesn't follow the rules of written grammar, but "A pathetic view" or "What a pathetic sight" would read a lot better.
(2/2) *Main Challenge: done.
(2/2) Subchallenges: Done.
(2.5/3) Appeal: Primarily a Txmmy and Spike card. Jxnny might want to do something silly by pumping the opposing creature's toughness?
(3/3) Elegance: Fairly elegant.
(1.5/3) Viability: I can't see this card justified in GU without a ton of context. When blue removes opposing creatures it leaves something behind for that creature's controller - a token, another creature from their library, usually that sort of thing. It's not concepted as killing but as transmogrification. Exiling an opponent's creature and then getting a reward for your own creature is just unacceptable in that color combination - Phyrexian Ingester is a color pie break even with heavy flavorful and mechanical context. To anticipate an argument, I do not think it's valid to say this effect is analogous to gaining control of a creature. It's also borderline in rarity terms. I think a card like this would be more likely to be rare than uncommon (based on things like Trap Essence) unless part of a larger context like an MMNN-cost cycle.
(3/3) Balance: Strong removal but not easy to cast.
(1.5/3) Uniqueness: Lots of precedent, feels like a "natural" design, reminds me somehow of Kalitas, Bloodchief of Ghet.
(2.5/3) Flavor: Very fine, but not grabbing me that hard.
(1.5/3) Appeal: "Fun" removal is up Txmmy's alley. Not as efficient as Spike would like and a bit straightforward for Jxnny but there are definitely situations when Jxnny wants something to fight a 1/1 vanilla.
(3/3) Elegance: Nicely elegant stuff.
(3/3) Viability: Classic Chinese-menu multicolor with green fighting and blue "make them a 1/1."
(3/3) Balance: Three mana is about what I expect to pay for this.
(2/3) Uniqueness: Plenty of precedent for "humiliating" and fighting alike, but putting them together in this precise way is new.
(3/3) Flavor: Just lovely.
(2.5/3) Appeal: I wish I could set the appeal to 3 just for appealing to me so much - I love exactly these kinds of build-arounds AND it uses my beloved Treasure tokens! Txmmy and Jxnny both see something to like, whereas Spike sees this as mostly a sideboard card and even then, has cheaper options to hose Eldrazi and artifacts.
(2.5/3) Elegance: Elegant overall even though "colorless nonland" is a bit stilted; I would have made this cost a little more, maybe drop the stats a little bit if necessary (2/2, 3/1?) and just had it hit colorless permanents.
(3/3) Viability: Colors and rarity seem pretty spot-on to me.
(3/3) Balance: Nothing objectionable here; basically a build-around rare with a few good functionalities.
(2.5/3) Uniqueness: Definitely precedent but definitely a unique ability suite.
(2.5/3) Flavor: Great name, good flavor text; the ability to melt down Eldrazi but not colored artifacts, while necessary for the challenge, messes up the flavor a bit.