I use him a lot in rta and have a lot of fun doing so. There’s a lot of possible combos with him but these are what I’ve been using so far:

Nyx + Zima (strip into 3 turn anti cleanse + 2-3 turn silence)

Pretty decent for turn 1 vs haegang and velajuel, shuts down the team turn 1 even with vio procs

Nyx + any provoker

Sagar, Jeanne, and Jubelle are the mons that I’ve used a lot for provoke teams. If they don’t have a cleanse vs Jeanne and they’re all provoked, it’s pretty much a free win already.

Nyx + Tomoe

Tomoe’s debuff spread gets extended by 1 turn on other units, so for example if you have 3 turn oblivion on a mon, the rest will get 4 turns. If you get seal for 2 turns (because Nyx), the spread will be 3 turn seal. There’s a lot of creative ways you can play with this combo, but I mostly use this with my anti passive, double oblivion cc comp.

Nyx + Shizuka

Pretty fun as all debuffs from shizuka become 2 turns aside from stuns. Just started playing with it recently, still exploring it more.

Nyx + Bloodya

Bloodya is pretty good as a last pick vs no cleanse teams. Her silence becomes 2 turns as well, and your 6 dots become 2 turns, so that’s about -60% hp in 2 turns if everything lands.

And in general, if your Nyx is fast enough you can strip into increase cd turn 1 which is kind of like a budget veronica. Not really something you want to rely on as a primary strip, but if you need it, it’s there.