FO one foe, Sky Drop the other. In turn 2 use Gravity, which locks out the sky dropped mon, and the other mon can get an attack off. Dragonite needs to survive this, and it happened 2 or 3 times that he didn’t. If he survives, one normally is in really good shape, even if the active enemy mon still threatens Nite (like outspeeding and KOing). If so, just protect and bring Infernape in. During his FO, Nite can use DD. It’s not uncommon to do this cycle one more time back to Sableye, or even more, if necessary and possible. (One time I faced +4Def Vaporeon and I used in total 8 FOs, during which it always saw the guaranteed KO with Ice Beam, until I had enough boosts to oneshot it. Another time against a Suicunes Pressure I decided I need PP ups on FO afterwards). Leer also helps (Leer is incredible, in general) to start the sweep, especially if you are pressured and cannot setup another DD. If Nite can KO sth on his own, then I switch in the other FO mon, to have FO ready for the incoming mon. Or if the FO-mon dies, but Nite can KO the active mon next turn I can bring in Scizor to setup a SD. Sometimes a bit of extra damage is needed, but Protect + one more Leer and one is good to go. Overall when this is rolling, there is hardly anything that can go wrong. No danger from QC because of FO, and I also can set Gravity to avoid Bright Powder/Snow Cloak etc. if necessary.
Of course that is worth nothing if the lock fails. The front row is designed to minimize these chances. Nite needs speed, because if both mons outspeed it this means it needs to survive 2 potential attacks in order to save the lock. In such a case FO+DD may be an alternative strategy, applied e.g. when facing 2 dragons (likely followed by protect + switch in Infernape to come out on top). Dragonites EVs are such that it survives Haxorus Outrage. Faster Blizzard users are handled by Sableye: Froslass, Cryogonal, Jynx are OHKOed with Sucker Punch (unless Sash), or Fake Outed in the case of Suicune and Articuno. Speaking of which, Sucker Punch! I really think Dark Gem is THE item for Sableye in the subway. Sash or Sitrus I feel often are wasted. With the Gem, Sableye actually hits a bunch of relevant KOs: Espeon, Gengar, Froslass, Starmie, up to Latios234, to which this is EVd for.
Priorities for the Sky Drop target are: Hard hitting mons slower than Nite. Steels and defensively boosting stuff, Clear Body, mons with strong EQ (killing their locked partner, happened 2 times). Curse can be problematic, especially when run by a Steel type. Despite Leer, Nite may not be able to overpower them while they can KO after few Curses. Sometimes one quickly has to get Infernape in before they get out of control. These are the qualities that brought Infernape to the team: FO, being fast, and hitting Steels (and Ice and Stones – Nite approves). Infernape is a backbone of the team.
Ofc strong crits are the most common sorrow. I remember 2 times Nite got OHKOed, one time against dragons, the other against Ice. That’s quite terrible, being at 3vs4 having only Gravity to show for. At least against Ice the remaining offense is superb.
Other things that can stop or break the lock include: Switcheroo, Roar, Encore, Perish Song, Taunt, Gastro Acid, and Status on Sableye. Not too problematic mostly though.
Some more words to Dragonite: First I thought it just needs to survive and leave the work to its mates. But actually with DD it is the MVP, and the others main job is to support him. I think the ability to boost speed+attack really sets him apart from probably the more obvious choice of a Sky Drop mon: Tornadus (T). I first tried Tornadus-I in this role (70 wins), and the higher speed was highly valuable. But as a battle continued, one is struggling a lot more against the unknown backrow mons. To be fair, the streak with Tornadus was without a second FO in the back. Still, I think Dragonite is superior (Lum also being a factor, which Tornadus probably cannot afford to hold).
Lastly: Scizor. He was significantly less used compared to the others. Often it felt like a superflous luxury to be able to use SD. It still was crucial to have him, and I don’t know what could be a better replacement. If only his Bullet Punch went after Sableyes Leer. Luxury problems though.