Fight on clean ground
Keep lava, cliffs and props outside your strafe loop.
Island 5 · Volcano · Optional endgame boss
Use the Scientific Boss Lure from an open Volcano shoreline. This is an expensive optional encounter, so buy it only after your late-game weapon, ammunition and healing are ready. Keep the shark in view, strafe across its approach, reload after separation, and do not let lava or props close your movement lane.
Trigger → fight → hand-in
Goblin Shark is optional. Do not delay the whale route if the late-game boss lure would empty your budget.
Walk the landing lane first and identify where you will turn, reload and heal.
The regular Scientific Lure catches Volcano fish; only the Boss version starts Goblin Shark.
No NPC needs this body for the ending route. Record it before selling or cooking.
The fight
Pufferfish wins when you stop moving. Your job is to keep clean sand ahead of you and a palm trunk between each charge.
Keep lava, cliffs and props outside your strafe loop.
Move laterally and keep the boss in view instead of backing along its line.
Make a safe gap, reload, then reapply pressure before the escape indicator falls.
If the lane is bad, reposition before casting rather than wasting the lure.
Fix the failed run
Use the symptom, make one correction, and go again.
Check the name: you need Scientific Boss Lure, not Scientific Lure.
Scout a different shoreline and keep the entire loop on clean ground.
Return after upgrading your primary ranged weapon and stock a larger reserve.
Goblin Shark is optional and has no main-story hand-in.
Fast answers
Scientific Boss Lure on Island 5 · Volcano.
No. It is an optional endgame collection and money target.
Confirm the Fishipedia entry, then sell, cook or keep the catch; no NPC hand-in is required.
Gameplay route checked 2026-10-02 for Patch 1.1.3.