Suicune has the best defensive stat distribution of any water type. Two thing hold it back from being ubers, that's the lack of recovery and pretty bad ability. In OM i gets the ladder and better stats.Implemented Mega Stone viability rankings in the OP with Lukethehedgehog's help.
Can't copy/paste xJownage's latest version of the Pokémon Viability Rankings. :(
The Council will be voting on Shadow Tag in 2 days, given the lack of discussion. Anybody who has anything else to say, say it before then.
Mega Mawile gets a boost in firepower through Medichamite, not to mention Speed, but I have difficulty imagining it being much more highly ranked than whatever it is in Ubers -maybe even less, due to all the other things running around.
No commentary on Suicune. Haven't seen it in action, and have never fully understood what factors lead to it being so powerful in so many OMs.
No commentary on Meloetta. I dunno where its utility lies relative to other Pokémon -it can presumably do shenanigans with Pirouette Forme, but these seem gimmicky and unhelpful, and otherwise it has to compare to myriad other Psychic types. Is the added Normal typing worthwhile? It does provide immunity to Ghost... dunno.
Rhyperior obviously appreciates all the type-changing Mega Stones. Too bad there's no type-changing Mega Stone with Regenerator to grant it healing...
I don't see what you'd use Mesprit for. It's generally going to be outclassed by Azelf or Uxie in any given role you try to build it for, not even looking at other, less similar Pokémon.
... oh wow, Hippowdon actually getting use out of Fire Fang in a meta. Huh. Lets it potentially beat Skarmory, in fact.
4 Atk Hippowdon (Red Orb) Fire Fang vs. 252 HP / 252+ Def Skarmory in Sun: 168-198 (50.2 - 59.2%) -- guaranteed 2HKO
Of course, Skarmory can, in turn, be running its own Mega Stones -Sablenite, say- but this is pretty impressive, when normally Skarmory can essentially ignore Hippowdon! And this is from a Physically Defensive Hippowdon, at that. A lot more bite than I was really expecting from it, honestly.
I'd like to retort on my mega mawild nomination, Hippowdown and don sorta... Wall it to death. C-B is fine