>>36503656Remind me again how Deoxys-Attack had no effect on the playstyle of Deoxys-N?
>>36503661Ultra-Necrozma is only good if it gets time to set up, otherwise it isn't fast enough to deal with Ubers' revenge killers, or quite strong enough to punch through anything with any amount of bulk.
If it runs two set up moves, which it needs to in order to sweep, unless it's just cleanup, it has severe 4MSS. Photon Geyser, Moongeist, and Dragon Pulse would be okay, if it could run all three.
Necrozma only gets Calm Mind on the special side, which means if it wants the superior special set, it has to run the worse boosting move, but if it wants the better boosting move, it only gets Photon Geyser, and your choice of niche coverage.
It DOES have a nice niche of being able to just delete any pokemon that doesn't resist Psychic, but even that takes a turn of set up at some point, if it gets outplayed you've lost it for nothing, and it takes up yet more resources that could have been used better elsewhere.
Ultra-Necrozma can't really run many other sets well, because they are directly outclassed by Dawn-Wings or Dusk-Mane. Anything regarding bulk is out, and it's only barely stronger than the forms in their on-stat.
What makes this messier, is that Dusk-Mane is a very convenient pokemon in terms of stats, moves, and typing. It does all of the cool things that Solgaleo does, and isn't spitroasted nearly as hard by P-Don, and can actually make plays, rather than yell angrily at Xerneas.
Honestly, the best way to use Ultra-Necrozma is as a late-game cleaning tool that is an auxiliary function of your Dusk-Mane, which means Timid is an awful choice. Probably less useful than Leftovers, mind.