Mine is probably not a unique strat but it works, and just adding it for other's that don't have 2 Nexus Whelplings like me. I do keep a Nexus Whelpling in the 3rd slot in case of bad RNG, but not had to use it yet. The fight lasts around 7-8 rounds.
1. Unborn Val'kyr
: Curse, Unholy Ascension
2. Nether Faerie Dragon
: Life Exchange, Moonfire, Arcane Blast until dead