If you're MF'ed then like Brolic said, just [tank the hits] if you can't get past MF.
If you get rooted, spam Twin Moon Slash. I usually can knock down a FB and stall em before they manage to do anything.
and IVSaKeN - Twin crits 1k dmg at least for me. Wouldn't call that pathetic damage when you can't move really.
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