From Bulbapedia, the community-driven Pokémon encyclopedia.
Mirage Island (Japanese: まぼろしじま Phantom Island) is a hard-to-reach location in Hoenn, found on Route 130 in Pokémon Ruby, Sapphire, and Emerald. It can only be visited under highly rare circumstances.
In the games
The island is inhabited by wild Wynaut, which range from level 5 to level 50. Most notably, the island also bears a tree where the one and only Liechi Berry in the game can be picked. This is the best Berry for Pokéblocks, and will produce Gold Pokéblocks. It can also be used as a held item in battles, where it will increase a Pokémon's Attack in a pinch.
Every day, a random number between 0 and 65535 is generated by the game. If this number matches the first two bytes of the personality value of any Pokémon in the player's party, then Mirage Island will appear. (Consequently, Mirage Island can be made to disappear and reappear for that day by removing and putting back the matching Pokémon in the party, and Mirage Island will disappear at the end of the day barring the unlikely outcome of two matching numbers being generated in a row.) This makes Mirage Island's appearance even rarer than encountering a Shiny Pokémon, although the probability increases with the number of Pokémon the player has. The odds of a single Pokémon activating Mirage Island is 1/65536; this chance is increased to approximately 1/10923 if the player has a full party.
An old man in the southeastern hut in Pacifidlog Town will tell the player whether or not he can see Mirage Island, allowing the player to check if they have a matching Pokémon without having to leave the town. Since Mirage Island's number does not change throughout a given day, it is possible for the player to freely move Pokémon between the boxes and the party while attempting to check if any Pokémon in the party matches the Mirage Island number.
Two random bytes ("Mirage Island bytes") are generated for the day once any button is pressed on the start menu, and will last until the start menu is accessed again past 00:00 (midnight) of the next day. Even though play time has nothing to do with the real-time clock, a game that has reached the maximum time of play (999 hours and 59 minutes) will always generate Mirage Island bytes of 0. Additionally, if a game's internal battery is dead (causing the real-time clock to stop functioning), then new Mirage Island bytes will never be generated, causing the Mirage Island number to permanently stay at whatever value it was before. Currently, it has not been precisely documented what happens to a game which has both a dead internal battery and a maximized play time.
Route 130 with Mirage Island
Route 130 without Mirage Island
|| 5, 10, 15, 20, 25, 30, 35, 40, 45, 50
| A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
In the anime
Mirage Island in the anime
In Who, What, When, Where, Wynaut?, Ash, his friends, Drew, and Team Rocket landed on Mirage Island after Team Rocket's submarine crashed. May and Drew got separated from the others and ended up nearly drowning when Drew passed out, before being saved by the resident Wynaut population. Team Rocket tried to steal the island's rare Liechi Berries, but were ultimately stopped. The group was eventually shipped off the island by a man named Roderick, who also gave May some Liechi Berries to be used as Pokéblock ingredients.
While the island does appear on maps, the whirlpools around it make it almost impossible to get to or off the island.
In the manga
In the Pokémon Adventures manga
In Talk About Timing, Treecko, Wally rescued a man searching for Mirage Island in Pacifidlog Town from being washed away by Kyogre's storm.
In A Royal Rumble with Regirock, Regice and Registeel II, Ruby and Sapphire were washed up on Mirage Island, where they met Juan, Tate, and Liza. Juan explained that the time on the island advances at a different pace than in the outside world, resulting in the two having been unconcious for 21 days. The time on the island does not always travel at a constant speed, and when the time on the island goes normal, one can get on or off the island. While staying on the island, Ruby and Sapphire encountered the Plusle and Minun from the Abandoned Ship again and trained to become better at Double Battles, in order to be ready to face Kyogre and Groudon. After their training was complete, the Gym Leaders awarded Sapphire with the Mind and Rain Badges, before the two Pokédex holders left the island in Rayquaza Redemption II.
While Ruby and Sapphire fought against Kyogre and Groudon, and subsequently Archie and Maxie, Juan, Tate, and Liza observed the events from Mirage Island through Juan's Kingdra's water screen. In It All Ends Now VIII, when Ruby was revealed to be in possession of Celebi, Juan realized that Celebi's presence on the island explained why time had become unstable there when Ruby and Sapphire arrived on and left it.
According to Juan, Mirage Island is not the actual name of the island, but what people refer to it as.
In other languages