Updated June 2026
100 Days At Sea Co-op Strategy Guide
Co-op transforms 100 Days At Sea from a grueling solo endurance test into a coordinated island raid — but only when roles complement rather than duplicate. Four Sharpshooters without Medic sustain fail Ice Island cold drain; four Campers without DPS never clear Kraken. This guide covers team composition, Crewmate (+10% team XP) aura value, shared seed routing on seeds, individual code redemption from codes, and boss role splits for all six encounters on bosses. Written for squad play — distinct angle from solo beginner survival despite shared survival fundamentals.
Ideal Four-Player Composition
Slot 1 — Medic (30 Pearls): +15% health regen, Medkit stock manager, sustain anchor for Ice Island and Kraken long fights.
Slot 2 — Crewmate (25 Pearls): +10% team XP bonus, Flare Gun map markers for seed coordination, co-op progression accelerator.
Slot 3 — Sharpshooter (55 Pearls): +25% ranged DPS, Scoped Rifle, Frost Giant and Kraken primary damage.
Slot 4 — Soldier (45 Pearls) or Camper (25 Pearls): Soldier tanks Lava Guardian; Camper builds Container Shelter and Raft Expansion for team raft.
Flex swaps: Raider for loot+DPS on Desert/Shipwreck farms, Ancient Squid for Kraken water phase, Fire Mage for Volcano AOE.
Pre-Game Co-op Setup
Join same server seed before Starter Island departure — share seed ID in voice chat. Document layout on seeds.
Codes redeem individually — STRANDEDDEVS companion chests are personal not guild bank. Share code list from codes in chat day one.
Assign island roles: Adventurer scouts, Merchant sells team loot, Treasure Hunter marks chest clusters on Bermuda prep.
Voice comms for boss phases — boss fights callouts require real-time coordination especially Kraken tentacle phases.
Co-op Boss Role Assignments
Sand Worm: ranged DPS (Sharpshooter/Cowboy) + optional Medic. Melee players bait burrow — no tank required.
Ghost Captain: Soldier tank + dual DPS (Battle Buku + Sharpshooter). Medic backup heals during ghost phase.
Lava Guardian: Soldier face-tank fire waves, Fire Mage AOE adds, Sharpshooter boss DPS, Medic cleanse/regen.
Frost Giant: Sharpshooter weak-point sniper, Soldier soak slams, Medic vs cold tick, Seagull food passive on food manager.
Kraken: Ancient Squid water phase, dual Sharpshooter/Pirate surface DPS, Soldier/Medic anchor, full four-player mandatory.
Bermuda Entity: Hero or balanced S-tier DPS, Night vision, Treasure Hunter post-fight crates, Medic endurance.
Resource and Pearl Pooling Ethics
Pearls do not transfer — each player spends own 100DAYS and farmed Pearls. Coordinate unlock order so team has ranged before Desert, tank before Volcano.
Iron and Scrap Metal: designate Shipwreck farm sessions — Raider (+20% damage + raid loot) maximizes team Iron for collective Iron Armor checks.
Raft ownership: Camper builds on host raft or designated builder raft — agree before Raft Expansion consumes shared Wood stock.
Mystery Crates on Bermuda: Treasure Hunter on one dedicated farmer — share Ancient Relics for team endgame mods not personal hoarding.
Co-op Failure Recovery
Wipe on Kraken: regroup at raft, Grinder recycle failed gear, Medkit restock from crafting, retry same seed coords.
Player disconnect mid-boss: Soldier/Medic short — pause summon until fourth returns or downgrade to Frost Giant practice.
Undergeared joiner: delay Volcano until joiner completes Iron Armor — rushing Lava Guardian with three geared and one wooden raft player wastes team Medkits.
Solo fallback: if co-op collapses post-Kraken, Medic solo can finish Bermuda with stocked Medkits per survive day 100.
Frequently Asked Questions
How many players for Kraken co-op?
Four players strongly recommended with Scoped Rifle tier weapons and full Iron Armor. Ancient Squid helps water phases.
Best co-op team composition?
Medic + Crewmate + Sharpshooter + Soldier or Camper. Adjust Fire Mage or Ancient Squid for Volcano and Kraken.
Do codes share in co-op?
No. Each player must redeem SEAADVENTURE, STRANDEDDEVS, and 100DAYS individually on their own account.
Does Crewmate XP bonus stack?
One Crewmate per team provides +10% team XP. Multiple Crewmates waste aura overlap — pick complementary roles.
How do we sync island seeds?
Join same server instance on Starter Island. Share seed ID and document routes on map/seeds and tools/seeds.