@shinyakimura I don't think so, as far as I remember.
Veldora don't have ultimate skill atm, he will get one probably soon after his resurrection, while Milim already got it long time ago. So it's a bad match skill wise. Later in the story I think he's stronger, since he's sharing mana with Rimuru
@Firianath where's the asspull when you need it the most?... can't he just ask the improved great sage "how to beat milim" and get an easy answer like it was with the orc lord?
Near the end of the WN it was said Milim had the potential to eclipse even the true dragons because she inherited her father's ability to generate power near infinitely. Even Guy who could copy other skills would have a hard time beating her because he wouldn't have the same capacity to hold as much energy. But it comes with the downside of her going into a mad frenzy so she pretty much never uses it in the series
As far as powerscaling goes the true dragons are vastly more powerful then any of the current demon lords except for 3, one of them being Milim and even then they're in the same ballpark.
@storm_crow Oh yes, I've read the web novel and some parts of the light novel some time ago. I think I'm starting to forget some characters and events after reading so much shit lately. Thanks for remembering.
@Owyn You won't get an answer because in combat Milim is almost unbeatable. It's easier winning her by being her bestie than by fighting. If I'm not mistaken,
even end game Rimuru can't beat her. She is THAT strong. It's a perk of being the direct daughter of the first and strongest Dragon in the series.