A strategy similar to Crow Master can be used on Mahasti. As is grabbing her, staying a safe distance from her is the safest strategy, whilst bouncing off of walls into her for an attack that lets you out of her range before she counters, as she sometimes defends against the attacks. Another option is to jump over her, and then use the dagger to slice at her, then repeat. If she starts overpowering you, block, and run away. Be wary of her powerful kicks, which can shoot you off the block the two of you are fighting on.