Viperfish

Viperfish packs a lot of value into a small body. At C$450 per kg, an average of 2.5 kg earns C$1,125, ranking 315th of 742 documented fish by value. Its weight runs from 1 kg to 8.4 kg, with a maximum-weight rank of 479th of 663, and it gives 350 base XP. The value rank is far better than the weight rank, so the price per kilogram is doing the work.

It lives in Crimson Cavern and takes Minnow. Conditions are Night, Rain and Winter, so you need a cold, wet night to see it. The game describes a grotesque fish with oversized fangs prowling the cavern's depths.

Red Crabsquid is the other Rare fish in the same zone, so you may bring up either one on a good night. Four rods are sold in Crimson Cavern: the Evil Pitchfork, Scarlet Spincaster Rod, Ruinous Oath and Wicked Fang Rod. That is a wide selection, so the zone is also a good place to upgrade gear.

Verdict: a good money fish for a Rare. Minnow is a simple bait, and the Winter-night restriction is the cost: plan for it, bring Minnow, and treat each rainy night as a window to fish.