Seeing "HydreigontheChild" suddenly become "Isabelle" was as almost as shocking as being reminded people use Tornadus in this tier. As for my submission....
Zygarde-10% @ Choice Band
Ability: Aura Break
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Thousand Arrows
- Outrage
- Extreme Speed
- Toxic/Glare/Skitter Smack
Submitting Zygarde-10% (again) as a
check given it's one of the few mons in the tier (and on the VR) that naturally outspeeds Tornadus-Incarnate, given the use of Hasty nature makes Thousands Arrows capable of OHKOing when it otherwise wouldn't, and given Outrage OHKO even with a Def-neutral nature anyway. As frail as Zygarde-10% is, itemless STAB Acrobatics from Tornadus oddly isn't a guaranteed OHKO either. In fact, it has a lower chance to OHKO Zygarde-10% with Acrobatics than the OHKO risk that Thousand Arrows presents to its Hasty self:
Zydog's threats:
252 Atk Choice Band Zygarde-10% Thousand Arrows vs. 0 HP / 0- Def Tornadus: 274-324 (91.6 - 108.3%) -- 50% chance to OHKO
252 Atk Choice Band Zygarde-10% Outrage vs. 0 HP / 0- Def Tornadus: 364-430 (121.7 - 143.8%) -- guaranteed OHKO
Tornadus's threats:
252 Atk Tornadus Acrobatics (110 BP) vs. 0 HP / 0 Def Zygarde-10%: 219-258 (87.9 - 103.6%) -- 25% chance to OHKO
Since both Zydog's STABs deal with Tornadus rather handily, with Thousands Arrows being a guaranteed OHKO if it's taken basically
any chip damage, the last slot is pretty flexible too, which is nice for a check that stillgets to spam the move it already wants to spam 99% of the time anyway. Glare in particular also screws Tornadus over, however, if for some reason you don't want to just outright OHKO the least Genie and put it out of its misery.