To unlock the Third Sea:
Reach Level 4000: Grind through the First and Second Seas by completing quests and defeating bosses.
Craft the Heart of the Sea: Collect the following materials:
50 Logs (chop trees)
50 Fresh Fish (dropped by Fisherman enemies on Bubble Island)
10 Undead Ooze (dropped by Zombies on Zombie Island)
15 Angelic Feathers (dropped by NPCs on Sky Island)
10 Piles of Bones (dropped by Skeletons on Skull Island and Ghost Ship)
1 Sea King's Blood (dropped by the Sea King on Legacy Island)
Once collected, go to Fiore Island in the Second Sea. Enter the mansion, find the trapdoor on the left side, and speak to Jack Stones to craft the Heart of the Sea.
Summon the Kraken Tentacle: Return to Japan Island in the Second Sea. Near the docks in the Viridians area, find The Squid NPC. Accept the quest to defeat a Kraken. Behind the docks, find Altar Mysterio, an invisible NPC. With the Heart of the Sea in your inventory, interact with Altar Mysterio to summon the Kraken Tentacle. Defeat it within 6 minutes to proceed.
Access the Third Sea: Return to The Squid. Upon completing the Kraken quest, you'll be granted access to the Third Sea.
Level Range: 4000–4300
Bosses: Fugitive, The Deep One, Fishman King's Guard
Quests: Defeat 4 Deep One Villagers, Defeat The Deep One, Defeat Fishman King's Guard, Defeat 4 Deep Divers, Defeat Fugitive, Kill 6 Fishman Guardians
NPCs: Set Spawn, Sailor, Gacha, Black Market, Quest
Level Range: 4300–4400
Boss: Cyborg Gorilla
Quests: Kill 5 Jungle Gorillas, Kill 5 Wilderness Gorillas, Kill 5 Jungle Apes, Kill Cyborg Gorilla
NPCs: Set Spawn, Quest
Level Range: 4400–4550
Boss: Ocean Gladiator
Quests: Kill 1 Ripcurrent Raider, Kill 1 Tidal Warrior, Kill 1 Ocean Gladiator
NPCs: Quest
Level Range: 4550–4800
Bosses: Tempest Tidebreaker, Abyssal Swordsman
Quests: Kill 4 Deepfire Combatants, Kill 1 Electro Abyss Warrior, Kill 1 Tempest Tidebreaker, Kill 1 Abyssal Swordsman
NPCs: Quest
Tips: The Abyssal Swordsman has 285,000 HP and drops the Dominion Cloak with a 2% chance.
Level Range: 4800–5000
Bosses: Prisoner Of Gravity
Quests: Kill 4 Rouge Prisoner, Kill 4 Prisoner Buccaneer, Kill 1 Prisoner Of Gravity
NPCs: Quest, Dravhiel, and Juste
Tips: This island offers high EXP, Beli rewards, New Race (Demon) and New Fighting Style (Justice Fist).
Level Range: 4800+
Bosses: None
Quests: None
NPCs: Mikaru
Tips: To upgrade your Kioru sword to V2, defeat the following bosses:
Abyssal Tyrant
7 Tentacles of the Chaos Kraken
Deepsea Crusher
Drakenfyr the Inferno King
Then, speak to Mikaru in Luma Grove.
Acro Spear: Requires Acro Scythe. Crafted with 9 Acro Eyes and 1 Hydra Tail.
Saber V2 (Full Power): Requires Saber (obtained from the First Sea boss, Expert Swordsman). Achieve a 2 million bounty, then accept a quest from an NPC behind the Saber Lord Castle in the Third Sea. Defeat Saber Lord, then return to the NPC with Kraken's Cache and 5 Aqua Gems to obtain Saber V2.
Kioru V2: Requires Kioru(From 2nd Sea) And Killing Every Set Sail Bosses.
Boss Farming: Utilize the 2x drop chance game pass to increase the likelihood of obtaining rare materials and weapons from bosses.
Sea Events: Be aware of sea events like Sea Kings, Ghost Ships, and Hydra. These events spawn periodically and offer valuable rewards. The Legacy Pose game pass can help you track these events.
Bounty Hunting: The Third Sea is populated with high-level bounty hunters. Stay vigilant and be prepared for PvP encounters.
Material Collection: Gather materials for crafting and upgrading weapons. Some materials are rare and may require defeating specific bosses or completing challenging quests.
For a step-by-step visual tutorial on accessing the Third Sea and exploring its islands, you can watch the following videos:(I DO NOT OWN ANY OF THESE VIDEOS)