Halloween Nowi build ?

Swordbreaker to double fast sword units or Vantage to make her more enemy-phase oriented. You can also run the Desperation+Brash Assault combo but it can be impractical and difficult to set up for Arena.

Another option would be Life and Death and Renewal, keep her base weapon, and have the other three fliers run goad fliers, then use a speed seal. Only recommended if you realllly wanted a fast flier. Her weapon would let her flock to her fellow fliers and take their goads or herself, and provide hones as well.

I went for Escape Route (same IVs).