How to Fish: How to Beat the Tuna Mini-Boss on Island 4

The Tuna is a mini-boss in How to Fish that fights nothing like its size suggests. It moves aggressively, closes distance fast, and gives you almost no natural openings, so most players take steady damage while landing nothing. The fix is not faster reflexes. You beat it by tricking its aim.

Quick answer: Feint one direction to make the Tuna commit, then immediately dash the opposite way. It overshoots to the side you faked, leaving a clear window to fire. Repeat until it dies, using a fully upgraded shotgun or sniper rifle.

Where to find and summon the Tuna

The Tuna lives on the fourth island, which sits in the late portion of the game. You need to progress through and clear the earlier islands before you can reach it. Once you arrive, head into the shop on the island.

Buy the Professional Boss Lure from the Island 4 shop. This is the specific lure that hooks the Tuna, so you cannot summon the fight without it.

Attach the lure to your hook and cast your fishing line into the water.

Wait for the Tuna to take the bait and get hooked, then pull it out of the water. The boss fight starts the moment it surfaces, so have your weapon ready before you reel it in.

Why the Tuna is hard to dodge

The Tuna does not chase your current position. It reads your movement and predicts where you are heading. Start moving left and it aims for where you will end up on the left, then hits you mid-movement. Do the same to the right and you get the identical result. Straightforward dodging fails because the fish is already ahead of you.

That prediction is also the weakness. Because it commits to where it thinks you are going, you can send it the wrong way on purpose.

How to beat the Tuna with a feint

Nudge slightly to the left so the Tuna reads it as a full move in that direction. You only need a small motion to sell the fake.

Quickly reverse and move to the right. The Tuna commits to the left and goes flying past where it expected you to be.

Fire into the fish during the opening its overshoot creates. This is the only reliable window to deal damage.

Repeat the feint-and-punish loop. Every cycle strips more health until the Tuna goes down. You can mirror the trick to either side, so keep alternating if that feels smoother.

Note: The Tuna carries 100 health, so shots that hit hard shorten the fight and reduce the number of feints you have to land cleanly.

Best weapons for the fight

Both recommended weapons work best when fully upgraded. Your choice mostly comes down to how much money you have to spend.

Weapon	Best for
Shotgun	Players short on money; hits hard once fully upgraded
Sniper rifle	Players with cash to spend; strong single-shot damage when maxed

What happens after you win

The Tuna sells for $2,000, but it is also the bait you need for the terrorizing bird boss on the same island. Whether you land it or kill it, the fish is always consumed once you use it. The Professional Boss Lure has a durability roll, so it may survive the catch and let you fish up another Tuna if you plan to farm or move straight into the seagull fight.

If the Tuna keeps clipping you, the cause is almost always the same. You are dodging cleanly instead of faking. Sell the feint first, wait for the overcommit, then shoot. Once that rhythm clicks, the fish that felt impossible to dodge becomes one of the easier openings to punish.