I do not know about a hag fish but has anybody ever tried Monkfish ? It taste like lobster or it is called poor mans lobster. I had it at Fertita's and really liked it. I purchased some from a local seafood market and I cooked it and it taste like rubber.
These guys live at about 1500 feet deep in the ocean and are not that nice to look at !
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Maranatha 
Mat 7:14 Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.