Units used: 5* Sanaki, 4*+8 Felicia, 5* PA!Azura, 4*Narcian
Sanaki
Triangle Adept 3/Swordbreaker 3/Hone Atk 3
Rauorblade+/Draw Back/Draconic Aura
Felicia
Attack +3/Desperation 3 - okno use Bowbreaker/Breath of Life 3/Quickened Pulse
Poison Dagger/Reciprocal Aid/Iceberg
PA!Azura - Dance, Uror, Drive Res 2
Narcian - Emerald Axe, Lancebreaker 3, Attack +3, Vengeance
Felicia needs Bowbreaker to double Takumi, I used QP Iceberg and Poison Dagger to improve her damage output. For some reason I did not realize this and hit 46 speed (Uror buff + Sanaki S Ally Support) to naturally double Takumi.
Sanaki can be replaced with a Brave archer or similar red mage, they only need 30 speed or Axebreaker to quad/double the axe cav.