You failed.
Dagahra was surrounded.
The Vampire's Mist ability was truly broken. No, in theory, no Vampire would ever dare to do something like that.
After all, as a Progenitor, Dagahra's Mana control was countless times better than any other opponent Nux had ever faced. The Vampire's Mist ability's weakness was Mana, once the Vampire, in his Mist form, is captured using Mana, the battle was over.
If a Vampire is captured in his Mist form, he would not have the physical strength to resist and break through the Mana binding him, it wouldn't be wrong to say that a Vampire caught in his Mist ability is completely at his opponent's mercy, even being captured and trapped inside an artifact for eternity was also possible.
This was also the reason Vampires were extremely cautious whenever they used the Misting ability.
Especially against an opponent who had stronger control over their Mana.
But for Dagahra…
That option wasn't possible.