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Even before that, it was still highly centralized as you to deal with the titans of the game. Note: swagger was banned in Gen 6 cause klefki was good at it (outclassed liepard, sableye, and thundurus in swagplay) and the meta became more tolerable unlike the HO nature of gen 5
Its funny how you say Ou is centralized, when ubers is much more centralized to begin with. You see very similar teams and real common sets for uber pokemon.
Okay...... This only works if your opponent has a cofagrigus otherwise, your team has no answer to mega- zard x, mega pinsir, talonflame, mega-medicham once your cofagrigus is weakened. Also, you have no switch ins for mega- gardevoir as Chansey takes a lot of damage from mega gardevoir's psyshock.
Mega pinsir might run earthquake for electric types, dragon dance or banded dragonite always ran earthquake even in gen 5, terrakion has ran earthquake in the past from electric types and the eq/stone combo so aegislash is not the sole reason.
Attempt at stall? Seems more like a balanced team. For stall in Uu, Forretress is a good hazards setter, Crocune can be used as well as a defensive sweeper if your into that.
So many flaws and not enough defensive core to stand against hyper offense teams. Xerneas, fairy Arceus , Stalltwo, Extremekiller, RestTalk Ogre, Darkrai, Mega-Blaziken, Mega-Gengar, Giratina all really can handle your team or atleast in my mind.
Scarfed special xerneas, specially defensive fairy arceus and choice scarf zekrom will probably be a bit difficult for you to take on at times with your team.
Im pretty sure someone with a ferrothorn won't stay in with a victini against them even in rain. However if ferrothorn leech seeds and predicts well and with hazards, you never know.
Physically defensive groudon, choice scarf kyogre, wallceus, lugia, giratina-0, and tyranitar with dragon dance in ubers is horrible as it is still slow and without a spd spread, darkrai and mewtwo destroy it with aura sphere and focus blast.
Ive tried using a starmie in ubers. It really is not that good. It has good typing to handle standard mewtwo but it is almost complete garbage in a tier riddled with powerful attackers that outspeed it.