I am interested in the former OU Pokemon, who were below the 3.41% cutoff on the Prebank Nov 13 statistics :
The first group is weather setters and weather abusers - Politoed's downfall is the biggest surprise due to the huge weather nerf. Alongside Ninetales and Hippowdon, UU initially will have all four weather's automatic setters. Rain offense may rampant with Toxicroak and the swift swimmers such as Uu's already top tier threat Kingdra (Who's also got his Sniper ability buffed ) and others like Ludicolo and Kabutops. Gastrodon may be used in UU for the same role it was used in OU, as to stop this newly rain madness that might fall upon the tier. If not, I can imagine Gastrodon falling even lower than UU, if say Politoed would be banned to BL. Venusaur is still locked in OU, due to it's Mega form but Ninetales can be partnered up with other great Chlorophyll users such as Victreebel and Sawsbuck. No fire types have yet to fall from OU, but UU's hard-hitters like Darmanitan, Victini and Chandelure (if it won't rise to OU) will highly enjoy the sun boost. Donphan was considered the best spinner, alongside Forretress, to sun teams and now is being outclassed in the sunless OU. Hippowdon can balance the incoming offensive play styles with his amazing bulk and walling capacities, alongside the defensive nature of sandstorm. The sand may benefit rock types like Rhyperior or Cradily or be used offensively with Sand Rush users like Stoutland (who got 10 more points into his Attack stat) and Sandslash.
The second group is dragons - With the newly dragon nerfing type, it could be guessed that some of the mighty dragons, previously roaming freely in OU, would fall. Haxorus was anticipated to fall already in the late stages of the BW2 metagame, but Salamence is quite the surprise. The former Mold Breaker laughs at what could have been the best counter, Bronzong and the latter can be offensive on both spectrums. If they both won't be banned to BL, it would only be managed by uprise of Fairies like Granbull. The downfall of both will dictate the metagame and will encourage offensive play style.
The third group is trappers - it seems they are no longer needed as much in the OU metagame. Each of the falling two seemed to have quite the specific team prototype to function in. Magnezone in offensive dragon teams, the DragMag combination, and Dugtrio mainly in sun teams. Both type of teams have become massively weaken in the generation shift and so the trappers usage is accordingly. Magnezone may enhance the offensive shift to UU by partnering with Haxorus or Salamence. It may also be used to check them, as it resists their stab and their fairy-type coverage. Dugtrio can no longer trap Heatran or Tyranitar but it might find some usage trapping steel types or helping to win weather wars.
The last group can be called bulky offense and is constructed from Conkeldurr, Metagross and Reuniclus. Metagross can be a fairy type killer, to partner up with the mighty falling dragons. Like Magnezone, it might be used to check them. The Agility set seems to be terrifying in this environment more than ever so it won't be necessarily bulky. Reuniclus and Conkeldurr however might shift the metagame into a slower pace of offense with Bulk up/Calm Mind. Trick room abusing sets may be viable and hard to stop.
What do you think of these suspects of becoming UU's new toys ? The Release of Pokebank might prevent whose falling ?