Boss Guide · 05
Mutated Bowhead Whale Boss GuideHow to Fish — Final Boss, Island 5 (Volcano)
The Mutated Bowhead Whale is the final story boss in How to Fish, fought at the volcano on Island 5. Getting to it is a two-step setup: you first catch and defeat the normal Bowhead Whale, then throw its body into the volcano to trigger the mutated version. The final fight is the hardest in the game — the whale slams the ground, its body drops lava, and it punishes the two mistakes players make most: running too far and rushing back in. This guide covers the whole trigger chain, the endgame gear, and the rhythm that wins the fight.
How to Trigger the Mutated Bowhead Whale Fight
The Scientist & the Five Volcano Fish
The trigger starts with the scientist in a yellow hazmat suit at the volcano. He wants help catching a large whale for an experiment. The full chain:
- 1
Talk to the scientist in the yellow hazmat suit at the volcano — he wants help catching a large whale for an experiment.
- 2
Catch five fish native to the Volcano using the Scientific Lure, and feed them to him one by one. He then gives you the Fish Bucket.
- 3
Use the Fish Bucket as bait to bring up the normal Bowhead Whale — a boss fight on its own. The moment you see it fly into the air, run as far away as you can.
- 4
Put the body in your inventory, climb the volcano using the wooden planks, equip the carcass, and throw it into the volcano — this starts the final boss fight.
Won't Start? Check These First
- Did you feed the scientist five volcano-native fish? The Fish Bucket only appears after all five hand-ins.
- Did you defeat the normal Bowhead Whale first? The mutated version does not appear until its body goes into the volcano.
- Are you missing the volcano climb? The whale carcass has to be thrown in from the top, via the wooden planks.
Final Boss Gear: What to Buy Before the Fight
The final fight is where the game wants you to have one fully developed ranged weapon:
Assault Rifle
The endgame gun, and the recommended pick for this fight. Buy it before the final boss, once you are holding around 20,000 coins, and take every upgrade you can afford.
Fully upgraded SMG
A workable alternative for a speedrun clear.
Healing Items & Food
Stock as many healing items as you can carry — they are what save you after the whale lands a hit. Eat before the fight so you are not constantly stopping to eat in the middle of it, which stretches the encounter and gives the boss more chances to punish you. In co-op, bring a teammate's revive safety net too.
Whichever you bring, concentrate on one gun — do not spread your coins across several half-upgraded weapons. If your shots are missing as the whale moves, fix control before buying more damage; if you are dying while reloading, rethink the reload window rather than the gun.
How to Beat the Mutated Bowhead Whale
The Rhythm: Read, Move, Watch, Shoot
The final fight has a deliberate rhythm. Do not rush back toward the whale the instant its landing attack is over — it can still move aggressively after coming down. Follow this loop:
- 1
Read the attack as it starts.
- 2
Move through the landing, keeping enough distance to survive it.
- 3
Watch the follow-up — see where the boss is actually going.
- 4
Shoot once the space is safe again.
You do not need maximum distance. You need enough distance to understand what is happening.
The Slam: Run When It Flies
When you see the whale in the air, run as far as you can — if it lands on you, the body slam will mostly kill you in one hit. This applies to both the normal and the mutated versions. The landing is survivable at range; it is not survivable up close.
The Lava & the Volcano Boundary
Lava
The Mutated version drops lava from its body, and getting burnt by it can kill you instantly. Keep your distance from the falling lava as well as from the whale itself.
Volcano boundary
Stay inside the volcano encounter area. If you pull the whale too far away — for example by sailing the boat out — the boss despawns and the fight resets. Make space, but make it inside the intended arena. Do not treat the boat as an escape mechanic.
After the Fight: Fin, Key & the Ending
Keep the Fin
Defeating the Mutated Bowhead Whale is not the end of the step. Pick up the Fin and return it to the scientist in the hazmat suit.
The Military Boat Key & the Ending
The scientist gives you the military boat key in exchange for the Fin. The military boat takes you to the mainland, and the credits roll. You can keep playing on the same save afterward to finish your fish collection and try the casino skins.
Mutated Bowhead Whale Tips, Mistakes & Tricks
Why You Keep Losing to the Final Boss
Dying to the body slam
→ You are too close when it lands. Run as far as you can the moment it flies into the air.
Dying to lava
→ You are standing in the falling lava. Keep distance from the orange drops, not just the whale.
The boss suddenly disappears
→ You pulled it out of the volcano arena, and it despawned. Stay inside the encounter area.
Dying right after it lands
→ You rushed back in. Wait to see where the whale is moving before you shoot.
Final Boss in Co-op
Co-op makes the final fight noticeably easier — the Bean speedrun notes suggest bringing friends specifically for this one. A teammate can revive you if the slam or the lava catches you, and one player can bait the whale while the others shoot. As with every boss, let the host turn in the quest for credit, and warn teammates before throwing Dynamite — it damages everyone.
Co-op guideSpeedrun & Achievement Tricks
- Bean speedrun (finish the game in under an hour): cook the Albatross meat in the lava to sell for a profit, buy the SMG suppressor and a Scientific Lure, and use Dynamite to collect the five volcano fish fast. Enter the final fight carrying only your weapon and healing items.
- Handyman achievement: this is the one the final boss exists for. Defeat the Mutated Bowhead Whale with the final blow landed bare-handed. Unequip your weapons before the arena loads — if the cutscene catches you holding a gun, you will panic-fire and ruin the run. Stop shooting a little before the whale is dead, then finish it with fists.
- Easy and Handyman do not mix: the Easy achievement (kill any boss within 10 seconds) is better done on a smaller, replayed boss — do not try to combine it with the bare-hands final kill in the same attempt.
Common Final Boss Mistakes
- 1
Bringing a half-upgraded weapon instead of one mature build.
- 2
Standing close when the whale is in the air.
- 3
Chasing the lava or ignoring it while shooting.
- 4
Sailing the boat out of the volcano and despawning the boss.
- 5
Rushing back to point-blank range the moment it lands.
FAQ
How do I get the Fish Bucket?
Catch five volcano-native fish with the Scientific Lure and feed them to the scientist in the hazmat suit, one at a time. He gives you the Fish Bucket after all five.
Why is there a normal whale fight before the final boss?
The scientist needs a normal Bowhead Whale for his experiment. You catch it with the Fish Bucket, defeat it, then throw the body into the volcano — that is what triggers the Mutated version.
Why did the boss disappear mid-fight?
You pulled it too far from the volcano. The whale despawns outside the encounter area, so keep the fight inside the arena.
What's the best weapon for the final boss?
The Assault Rifle, fully upgraded, with all your coins concentrated in it. A fully upgraded SMG also works for a speedrun.
That's the story
You've reached the ending — now finish the collection
Credits rolled, mainland reached. The optional content — every fish, every achievement — is still out there.