Tracing or stealing Shell Armor from Samurott was pretty good. Tracing or stealing Flash Fire from Typhlosion? Also pretty good. Now with Inteleon though, it has Sniper, and getting that ability for yourself isn't nearly so helpful.
What if we didn't copy it, though? What if we just...
took inspiration from it, see. Inteleon has its own way of enjoying criticals, and I have mine. But since my way involves getting to solo the raid with a Certified Meme Set™, I'd say it's well worth it.

Toxapex @ Covert Cloak
Ability: Merciless
Tera Type: Poison
EVs: 252 HP / 166 SpA / 92 SpD
- Acid Spray
- Sludge Bomb
- Recover
- Stockpile
Start by spamming Acid Spray not because it does much at this point, but because it's the most expendable move, with the highest PP supply, and it gets the snow turns over with sooner. Inteleon's preferred damaging reply is Blizzard, because by envelope math, 110 STAB resisted equals 82.5, which beats out the straight-up 80 from Dark Pulse. More often than not, though, it's going to waste a few turns using Tearful Look at the start, which will be inconsequential. However, if the damage does start to add up on Toxapex, try to deploy Recover around half health so you can get full value out of its limited PP supply. A max roll critical Blizzard deals 130 with this EV build (and it would take a whopping 20 extra EVs in SpD just to knock it down to 129), so you can be aware of the danger zone even though Blizzard has only the standard 1/24 rate, not the elevated rate of Snipe Shot which Inteleon isn't going to use in your lane.
Once the wipe happens, that's your cue to set up all 3 Stockpiles. It's important not to use any before then, because of how the move works--any previous stat boosts will be wiped, but the stockpile count won't, and the cap on that count will prevent you from getting any more boosts. By this point, the Mist has expired, so you can go back to Acid Spray and start getting stat drops from them.
After the SpD stats on both sides have been changed to their maximum extent, Toxapex is ready to become the offensive weapon it always wanted to be! Spam Sludge Bomb until you fish for the poison, then spam it some more. As always, dropping down close to half health is the cue to use Recover again and stay safe. It's possible to change the order so that you Sludge Bomb first,
then start getting the stat drops with Acid Spray, but I wouldn't recommend this unless you have a Bellibolt teammate or something, where they threaten to get a paralyze with Discharge which would spoil the whole raid--the reason being that the extra "Critical hit!" messages while you're using low-power moves waste time, and possibly reduce the number of turns that fit in the time limit. Note that if you successfully fish for a poison during "phase 1" of the raid, even though there are no negwipes anywhere in Inteleon's script, the act of putting up the shield will automatically erase any status condition on the boss and you'll have to re-inflict it, spending more PP in the process.
Once Inteleon is poisoned, all remaining Sludge Bombs of course have guaranteed criticals thanks to Merciless, and criticals mean you ignore all those Tearful Looks, getting a -0 vs. -6 hit. Wherever the threshold for breaking the shield is, try to envision 10% of the health bar above that (for comparison, the shield takes up 30% of the health once it's created, so the lower third of that), and once the boss's health drops below that point, it's time to charge: Start by recovering up to full health, then put up a red cheer, and now you can finally click tera on another Sludge Bomb, which should do enough damage to break the shield. After tera, you'll lose your resistance to Blizzard, which is why the Recover immediately beforehand. Then, once the shield breaks, you get a one-turn reprieve where Inteleon will not act (except perhaps for scripted actions, such as the renewal of snow and Mist, which you're long past caring about by now), so you get a big chunk of damage in for free. Two more Sludge Bombs after that should be enough damage to win--hopefully you don't face anything like double criticals on an unboosted move before you can get there, or if you do that there's at least enough time to cope with the drain and get off another attack.