Lucario~

of the top of my head
Riolu/Lucario
Arcanine
Zoroark
Entei
oh-ho
and Corviknight

im ashamed that I forgot to mention Lycanroc, both midnight and midday forms~
xwx

One I really want is Deino,huehuehue

All starters and their variants, Buizel/Floatzel, Riolu/Lucario, Mienfoo/Mienshao, Rockruff/Lycanroc (midday and midnight), Entei/Raikou/Suicune, Lugia/Ho-oh, Rookidee/Corvisquire/Corviknight are the ones that come to the top of my mind and that I've seen elsewhere in these comments.

Mienshao, Floatzel and salandit comes to mind.

I somehow imagine Suicune and Lugia would get a lot of traction.

Mewtwo and Phantump/Trevenant I think would be cool to use! I recently found a group of people who love Phantump, too :3

Mewtwo, Lugia, Suicune/ Walking Wake, both Articunos, Rhydon, Nidoqueen, Cobalion

Mightyena! :3

Luxray