Updated June 2026

Sand Worm Boss in 100 Days At Sea

Sand Worm is the first major boss in 100 Days At Sea — located on Desert Island in a canyon arena, gating mid-game Scrap Metal and Blue chest tier progression. Stranded Devs designed Sand Worm around ranged DPS and burrow-strike avoidance; melee-only loadouts fail without Flintlock Pistol or Sharpshooter support. This guide covers summon location on desert island, gear from crafting, class picks, and post-fight farming paired with boss fights.

Location and Unlock

Island: Desert Island (Medium difficulty). Arena: desert canyon — follow canyon markers from main dock after Days 10–15 progression.

Prerequisites: ranged weapon (Flintlock Pistol minimum), 20+ cooked meals, Medkits, Cactus Water for heat.

No Pearl cost to summon — gear check only. First boss in six-boss chain on bosses.

Gear Requirements

Mandatory: Flintlock Pistol (10 Iron + 5 Gunpowder + 3 Wood) or Sharpshooter Scoped Rifle starter if unlocked.

Recommended: partial leather armor, Medkits (5 Cloth + 3 Herbs + 1 Alcohol), Bonfire cooked meals not raw fish.

Optional: Crab companion (+5% gun) or Parrot (+7.5% gun) from companions.

Grinder and Crab Trap from Desert visit should be complete per harpoon fishing.

Fight Mechanics and Phases

Phase 1 — Surface strikes: Sand Worm lunges from sand — ranged DPS during exposed windows. Melee players chase unreliable targets.

Phase 2 — Burrow: Worm submerges — reposition to marked erupt points, avoid sand splash AOE. Medics sustain chip damage.

Phase 3 — Enrage: Faster burrow cycle — Sharpshooter crit (+10%) and Cowboy (+15% ranged) shine. Pirate hybrid maintains DPS if pistol ammo low.

Co-op: one dedicated ranged minimum, optional Medic, builder stays on raft food duty per co op strategy.

Recommended Classes and Team Size

Solo: Cowboy or Sharpshooter mandatory. Survivor reduces hunger during long kiting.

Duo: ranged DPS + Medic or Soldier for sustain.

Trio+: add Raider for loot bonus on post-boss Scrap Metal farms.

Avoid Battle Buku-only melee solo unless experimental — community wipes documented on boss fights.

Loot and Post-Fight Farming

Sand Worm clear unlocks confident Blue chest tier farming — Scrap Metal, Gunpowder parts on chest tiers.

Boss may drop Pearl bundles and combat mats — varies by patch; stack with daily defeat quests on daily quests.

Post-fight: farm Scrap Metal for Grinder upgrades before sailing to shipwreck island.

Common Mistakes

Attempting without ranged weapon — restart after Flintlock craft.

Understocking meals — burrow phases extend fight time beyond hunger bar.

Skipping Cactus Water — heat kills during long attempts.

Next boss in chain: Ghost Captain on ghost captain after Iron farm.

Frequently Asked Questions

Where is the Sand Worm boss?

Desert Island canyon arena — Medium difficulty island after Jungle Island.

Can I beat Sand Worm with melee only?

Not recommended. Ranged weapon is mandatory for burrow phases.

What weapon do I need for Sand Worm?

Flintlock Pistol minimum — or Sharpshooter Scoped Rifle if class unlocked.

Is Sand Worm the first boss?

Yes. Starter and Jungle islands have no bosses — Sand Worm gates mid-game.

What should I do after beating Sand Worm?

Farm Scrap Metal and Blue chests, then sail to Shipwreck Island for Iron.