Alright, let’s talk about the big one: the Mutated Bowhead Whale (aka the lava whale, volcanic whale, final boss, pick your favorite nickname). This is the last major fight in How to Fish, the one that wraps up the main story and hands you the keys to the military boat so you can finally sail home.
It’s chunky, it hits like a truck, it spits burning lava, and it will absolutely humble you if you stroll in underprepared. But once you know the setup and the rhythm, it’s doable, even solo.
All About Final Boss:
Get to the Volcano Island
You’re on the final island (the volcano, military area). Talk to the scientist in the yellow hazmat suit. He wants five local volcano fish, grab a Scientific Lure, catch them, and hand them over. That gets you the Fish Bucket.
Before you do anything else:
- Buy the Assault Rifle and fully upgrade it. This is your main damage tool.
- Stock your inventory with as many healing items as you can carry (food from the military base is perfect). Heal the second you take damage, this boss does not mess around.
- Optionally grab an extra Fish Bucket or two in case things go sideways.
Use the Fish Bucket to summon the regular Bowhead Whale. This is the mini boss phase. Fight it near the camp if you can. I think the dev has put this mini boss before the final one to let you get ready for the main monster. This mini boss is easier to defeat, but still one of the toughest creatures in the game.
Once it’s dead, store the carcass in your inventory. Do not try to sell it.
Climb the volcano, then yeet the Bowhead carcass straight into the lava. Boom, the Mutated Bowhead Whale spawns. Showtime.
Fighting Mutated Bowhead Whale
Stay in the volcano area. Do not try to boat it halfway across the map. Pull it too far and it can despawn, forcing you to resummon. Keep moving, keep shooting with that fully upgraded Assault Rifle and heal the moment you get tagged. A couple of hits can drop you, so mobility is your best friend.
Luring it toward the lava for some free environmental damage helps. Watch for the big landings and follow-up attacks, create just enough space to read what’s coming, then unload again. The fight has a deliberate rhythm once you stop panicking: move, shoot safe window, heal, repeat.
Can’t Kill It?
I tried multiple times to kill that son of a gun, but it is really hard and honestly I couldn’t do that near the volcano. The problem is that near that volcano, there’s no cover or way to escape those wild falling downs of Mutated Bowhead Whale. So, I thought why not use the house on island 4?
There’s a problem though, the game is trying to keep the fight near the volcano, if you get far away, the whale despawns.
So this is not the official way and has the risk of despawn. But I tried it and it worked. Good timing will help you here.
If you succeed in getting there with your lovely whale, try to wedge it against the casino door pillars so you can shoot from relative safety inside. You can also let it come in the casino (you should be lucky for this, be consistent), after entering, it’s too hard for it to get out. Stay out and just shoot that poor fat, big trash.
After Killing the Final Boss
Yes. you’re finishing How to Fish for real. Pick up the Mutated Bowhead fin and hand it back to the hazmat scientist.
He gives you the key to the military boat. Hop on, head to the mainland, and enjoy the credits. You can keep playing on the same save afterward for collection, skins, and whatever else.
Bonus: the Handyman Achievement
Want the Handyman achievement while you’re here? Good news, you do not have to fight the entire boss with your bare hands. That would be miserable.
The requirement is only the killing blow. So:
- Fight the Mutated Bowhead Whale completely normally with your Assault Rifle (and whatever else you like).
- Whittle its health down carefully until only a thin sliver remains. Leave a bigger cushion than you think you need, better to punch twice than accidentally finish it with a bullet.
- Unequip your weapon so you’re on bare fists.
- Move in and land the final punch.
That’s it. Handyman pops on the kill. If you overshoot and the gun gets the last hit, just resummon and try again. Co-op makes the timing a little more forgiving (teammates can hold aggro or revive), but it’s fully doable solo.
I think the only way to literally do this hard thing is the casino method I mentioned earlier. When you stick the mutual Bowhead Whale inside the building, it can hardly hurt you. Shoot and just finish the process with your bare hands (fists).
Warning: Using even the brass knuckles will cause you to lose the trophy. The only way to get the achievement is to kill the whale with FISTS.
