To kill the Bowhead Whale boss on Island 5, summon it with the Fish Bucket, then empty an upgraded assault rifle into it while sprinting away every time it launches into the air — then carry its body up the volcano and drop it into the lava to spawn the Mutated Bowhead Whale.
The Bowhead Whale is the brute guarding Island 5, the volcano island, and it hits hard enough to end a good run in a single landing. There’s no gimmick to the fight — it comes down to positioning and patience — and clearing it is what opens the door to the game’s true final boss.
The Bowhead Whale fight at a glance
| Detail | Info |
|---|---|
| Location | Island 5, the volcano island |
| How to summon | Equip the Fish Bucket as bait and cast into the water |
| Best weapon | Upgraded assault rifle or SMG |
| Main danger | Its airborne body-slam — a single landing can one-shot you |
| After the kill | Carry the corpse up the volcano and drop it in the lava to spawn the Mutated Bowhead Whale |
Key That last row is the part people miss: this fight is really the opening act, and everything you do here is setup for the mutated version waiting in the crater.
How to beat the Bowhead Whale boss on Island 5
Come in with a fully upgraded assault rifle or SMG, and bring the sniper rifle from Island 4 and any spare dynamite for extra burst damage. The fight itself is simple in theory — keep firing, keep circling, and never let the whale land on you.
STEP 1/6
Hook the whale
Equip the Fish Bucket — earned by bringing the hazmat scientist five Island 5 fish caught on the Scientific Lure — and cast into the water off Island 5 to hook the boss.
STEP 2/6
Open fire with your best gun
Switch to your fully upgraded assault rifle and keep firing; it deals the most damage of anything you can bring to this fight.
STEP 3/6
Sprint away the moment it goes airborne
When the whale leaps high, hit Shift and run directly away — never toward it — because a landing hit is fatal.
STEP 4/6
Dodge sideways and mind the hazards
Strafe sideways to slip its lunges, stay off the lava since it hits like a truck, and keep the friendly NPC out of your line of fire.
STEP 5/6
Pick up the corpse
Once its health bar empties and the kill registers, walk over and lift the dead whale onto your shoulders.
STEP 6/6
Drop it into the crater
Carry the body up the wooden plank path to the top of the volcano and drop it into the lava to spawn the Mutated Bowhead Whale.
After the kill, do not sell or scrap the whale’s body — that 12,000 kg carcass is the only bait that spawns the Mutated Bowhead Whale, so pocket it and haul it to the crater.
Video help
Beating the Mutated Bowhead Whale, the final boss
Dropping the body in the crater brings up the Mutated Bowhead Whale, the game’s actual final boss, and it’s a nastier animal in every way. It charges across the ground, leaps into the air like its smaller cousin, and scatters lava across the arena — and a couple of clean hits will drop you.
Fight it near the houses and the boat so you always have cover and a quick escape line, and keep moving; standing still is how the lava and the body-slams catch you. Before you trigger it, cook a stack of healing food and spread it around the arena rather than leaving one pile — seagulls will swoop in and steal anything you drop, and scattered food is harder to lose to a stray fireball.
When it finally goes down it drops the Whale Fin. Take that to the hazmat scientist and hand it over, and you’ll get the key to the military boat — the RHIB that finally carries you off Island 5 and into the endgame.
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Frequently Asked Questions
Does Easy mode make the Bowhead Whale fights easier?
Yes. Switching to Easy mode cuts how much health every creature has by roughly a quarter and drops the damage they deal by about half, which takes a lot of the sting out of both the Bowhead Whale and its mutated form — a body-slam that would normally kill you becomes survivable. The exact figures have shifted between patches, so treat it as a general difficulty cushion rather than a fixed percentage.
How do you unlock the bare-hands achievement on the final boss?
You have to land the killing blow on the Mutated Bowhead Whale with your fists. Wear its health down with ranged fire as usual, then when only a thin sliver is left, switch from the assault rifle to a weaker weapon like a pistol so you don’t accidentally finish it — that last shot is easy to overdo. Once the bar is almost empty, stop firing, fully unequip your weapon, move in, and punch it out. Brass knuckles don’t count as bare hands, so take everything off first.
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