To find Mirage Island in Blox Fruits, start by sailing in Danger Zones 1-6. The island has a higher chance of appearing in these zones, with Zone 6 offering the best chances. However, Zone 5 is often preferred due to better visibility.
While sailing, avoid all sea events except the Terrorshark Raid Boss, which cannot be skipped. Use a fast boat and the Portal V skill to move quickly and dodge events efficiently.
Timing is crucial. Search for Mirage Island within 2-3 minutes after sunrise and 2-3 minutes after sunset. Spawning the island too early or too late can make it difficult to complete the puzzle and find the blue gear.
Increase your chances by having multiple players in separate boats in the same area. Invite friends to join you in the search to improve the spawn rate of Mirage Island.
Ensure you meet all prerequisites, which include defeating Dough King for the Mirror Fractal, defeating Rip Indra, completing the Sealed King Quest, and having your race on V3.