What's the best nature for a competitive version of this thing?

Sassy

>>30109694
Jolly on everything best nature

>>30109694
you should specify your team and its role / moveset anon
you can't just randomly ask for a nature

>>30109694
modest w/assault vest

>>30109720
Naughty

>>30109694
lewd nature

submissive

>>30109753
I don't have a team yet. I'm just trying to catch them with the right natures in advance. Most of the UBs have been pretty straightforward with Naive/Timid/Modest, but I'm not sure if I should go Adamant or Modest on this thing.

>>30109694
I use an Adamant one w/ Heavy Slam. It hasn't let me down yet.

>>30109839
There are 2 Celesteela avaible in the game anyway, get a defensive one with -Spe so you can always swap its EV spreads whenever you feel to go mixed. Full offensive isn't that amazing but can be a thing too, but even with a defensive set with Fire coverage, Leech Seed and Heavy Slam / Air Slash it works well and delivers decent damage.

>>30109906
-Spe and +Def or +SpDef right?