How to trigger Spider Crab
The Spider Crab encounter is tied to Lighthouse. Prepare the Empty Beer Can requirement before you commit, then make space in your inventory and bring enough equipment to finish a messy fight. This is a quest encounter, so treat the catch as progress first and profit second.
Fight preparation
Land the boss somewhere open whenever possible. Fishing, carrying and combat all use the game’s physical systems, so a clear deck and a calm plan are worth more than a desperate last-second throw. Upgrade before retrying if the encounter is consistently overwhelming.
After the catch
Check the next island and lure tier before selling or spending your reward. Bosses are natural checkpoints: use them to reset your supplies and prepare a more dependable route for the next zone.