Scythe fish

Scythe fish are predatory virid fish found in deep open waters. Their sharp scythe-like appendages are evolved to slice off the limbs of giant virid squid squid, but they will attack and eat any kind of prey, including any humans unlucky enough to fall overboard from ships.

Scythe fish are most common in warmer tropical waters. They do attack whales, which is partly why whales are more commonly found in cooler waters of the northern hemisphere, and in the southerly Great Urash Ocean.