Yes, Raticate is quite good in ADV NU. I'll link a good handful of games from this NUPL which just wrapped up a couple of days ago.
Here are all of the rats in the tour, I'll specifically mark any games where rat did well:
Week 1 replays, rat did decent in both replays:
https://replay.pokemonshowdown.com/smogtours-gen3nu-692982
https://replay.pokemonshowdown.com/smogtours-gen3nu-693629
Not used by anyone in week 2
Week 3 replay (but they got instantly crit by a pikachu lol):
https://play.pokemonshowdown.com/battle-gen3nu-1876536046-oett3hxm2uvsca9n522ho7wsi3igjhgpw
Week 4 replays
Good rat replay:
https://replay.pokemonshowdown.com/smogtours-gen3nu-696178
Week 5 replays:
https://replay.pokemonshowdown.com/smogtours-gen3nu-697328
Good rat replay
https://replay.pokemonshowdown.com/smogtours-gen3nu-698227
Week 6 replay:
https://replay.pokemonshowdown.com/smogtours-gen3nu-698732
Semifinals replay:
https://replay.pokemonshowdown.com/smogtours-gen3nu-701742
I used raticate as my last in semis, but I didn't need to reveal it. But the team was based around weakening all of rat's checks for an end-game sweep.
And rat wasn't used in finals by me or SEA
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Rat is very popular in the tier. He runs about 3 different sets typically. A choice bander with double edge or return, shadow ball, hidden power ground, quick attack. A silk scarf user that bluffs choice band and runs the same moveset. Or a reversal sweeper that runs substitute, return, shadow ball, reversal and holds liechi berry. Raticate typically is used to clean up weakened teams; which is helped by the fact that he has the best speed stat unboosted in the tier and can OHKO Haunter which a lot of players save into the late-game. Choice band is less of a sweeper and more of a mid-game anti-Haunter mon and breaker. As far as the sets go, choice band is probably the most likely to go wrong, since if the opponent has a sableye or relicanth it won't get very far. But in certain matchups, like metang + haunter teams it can do well. If you want to learn the tier and play games with people, think about joining my discord:
https://discord.gg/muheMTaJvg . It inactive during the NUPL seasons, but now that it is over I will be more active on it.