Island Reef

Island Reef is a tropical archipelago destination reached through the Airport. It is an above-ground, water-heavy biome made up of long coral reefs broken by small islands, with cool water, native wildlife, and several unique points of interest. All vehicle types are permitted there, and because much of the map is open water, bringing a boat or other air/water vehicle makes exploration much easier. During hang out time, NPCs cannot travel to the Island Reef.

Each weekly visit generates a new map, but the drop-off point stays the same and matches the Airport location on the island. The map begins covered in dark fog, so the player must uncover it by moving around. The airship icon appears on the map and can be tagged to make returning to it easier. The airship is also safe to use when the area becomes dangerous late at night.

The Island Reef includes a number of special encounters and resources, including shipwrecks, shark statues, and reef-specific wildlife. Resources found there include Aquamarine, Pearls, Bee Hives, coral fragments and corals, several tropical flowers and seeds, fish, insects, and hand-collectable sea creatures such as Sea Sponge, Seahorse, and Triton's Trumpet.

• The Island Reef has a chance to spawn 1–3 shipwrecks per map. Breaking a shipwreck with a tool that can destroy hardwood, such as a Copper Axe, Iron Axe, or Chainsaw, will spawn an Alpha Shark. It is safest to prepare with strong food buffs, wear a Diving Helmet, and bring a weapon before breaking the wreck.
• Two Shark Statues spawn on each map. Feeding a Shark Statue 5 Old Keys awards a Treasure Map. Reading the map marks a red cross on the player’s map, leading to a buried Wooden Chest. Treasure Maps can be kept and used on later Island Reef trips, and they can also be displayed in the museum’s Display Case.
• After obtaining 20 Treasure Maps from the Shark Statues during a single Island Reef visit, the statues stop functioning as a source of maps and can be picked up as decorations. The 20-use limit applies across both statues for the entire trip.
• A Rotary Clothesline may also spawn in the water, usually 1–2 per map, and can be collected by diving down to it.

The reef’s insects and fish are distinct from those found on the mainland. Blue Tiger Butterflies, Common Crow Butterflies, and Purple-Winged Mantises can be caught with a Bug Net, while Blue Tang, Clown Fish, Humphead Wrasse, and Yellow Tang are caught with a Fishing Rod. Sea Sponge, Seahorse, and Triton's Trumpet are collected by hand.

A late-night hazard affects the entire biome. At 11 PM, the area shakes and rumbles as a warning that it is getting late. At 12 AM, or Late, the Island Reef begins emitting acid rain across the whole map, dealing 1 damage every 2 seconds. The airship remains safe from this effect, making it the most reliable refuge once the hazard starts.