Blight is one of the few bosses which do not require their dungeon's signature brush technique to defeat. While his inital quick-draw attack can only be made vulnerable using Veil of Mist, his second attack, where he raises a spinning circle of swords, can be hit with Cherry Bomb or Power Slash. Goldnail will then be made vulnerable, allowing you to damage Blight. It is possible one-cycle the fight by abusing repeated Fireburst Slowdown (via Inkfinity) and Steel Fisk Sake basic attacks.
In the Ark of Yamato, Blight has far less health, so he can be one-cycled using just SFS followed by a ground DI combo, then jump cancelled into a full aerial DI combo.