How to Fish: How to Upgrade Weapons at the Anvil

Weapon upgrades in How to Fish start with two things: money and the anvil. You raise a weapon’s damage by paying to “Sharpen” it, and the cost climbs each time you do it. Melee tools like the knife and brass knuckles are the first weapons you can improve this way in the early game.

Quick answer: Kill sea creatures such as Rock Crabs to collect money, walk to the anvil outside the lighthouse, and press E on the “Sharpen” option for a weapon. Each Sharpen raises that weapon’s damage number and charges more than the last.

Earn money by defeating sea creatures

You cannot sharpen anything until you have cash, and the fastest early source is combat. Cast your line from the dock, reel in a creature, and finish it off with a melee weapon. Defeated enemies drop money you can pick up directly.

Cast your fishing line into the ocean from the dock, then hold or spam the reel button when the “Reel In (Hold/Spam)” prompt appears to pull the creature in.

Player reels in a creature with the rod equipped in hotbar slot 2 and the Reel In prompt showing — Reeling in a creature from the dock with the rod selected in slot 2. Image credit: Dazed Games

Switch to a melee weapon such as the brass knuckles and attack the Rock Crab until you see the “Killed Rock Crab” message. Walk over the dropped money to collect it.

You can also pick up the Rock Crab and hand it to the NPC seated on the bench, giving you a second way to turn your catch into cash.

Rock Crab highlighted with the Inspect F prompt next to the character on the shore — Inspecting a Rock Crab before handing it to the seaside NPC. Image credit: Dazed Games

Sharpen weapons at the anvil by the lighthouse

The anvil sits outside the lighthouse. With money in hand, approach it and interact to open the sharpening options for your melee weapons. Each option is labeled “Sharpen” and lists a price plus the exact damage change it applies.

Walk up to the anvil near the lighthouse until the interaction prompt appears.

Press E on the “Sharpen” option for the weapon you want to improve. The menu shows the cost and the damage jump, so you know what you are paying for before you confirm.

Confirm the purchase. The weapon’s damage stat increases immediately, and the next Sharpen for that same weapon will cost more.

Note: Sharpening only raises the damage of a weapon you already own. It does not add reach or new abilities.

Sharpen costs and damage gains

Sharpen prices scale up with each level, and the damage increase per level is shown right in the menu. Here is how the early melee upgrades work out.

Weapon	Sharpen cost	Damage change
Knife	$14	16 → 18
Knife	$28	18 → 20
Brass Knuckles	$8	5 → 6

The pattern is clear. The knife’s second Sharpen costs double the first while giving the same two-point damage gain, so each level gets pricier for a steady increase.

Buy new weapons and bait at the lighthouse door

Upgrading is not the only way to spend your money. The weapon shop on the lighthouse door sells new gear and bait outright, so you can buy a stronger weapon instead of only sharpening what you have.

Item	Cost	Purpose
Knife	$45	New melee weapon
Hot Dog	$1	Bait for bigger crustaceans

Better bait like the Hot Dog lets you attract bigger crustaceans, which feeds back into the loop by giving you tougher targets and more money to sharpen with.

The whole process is a short loop. Reel in and kill creatures for cash, spend it at the anvil to sharpen the knife and brass knuckles, and pick up new weapons or bait from the lighthouse door when you can afford them. Because each Sharpen costs more than the last, it pays to keep a small money buffer so you are never one crab short of the next damage bump.