About it more descriptively :
Mirage Island is found on Route 130 in Pokémon Ruby, Sapphire, and Emerald. However, it can only be visited under highly rare circumstances. It is visited mainly for the one Liechi Berry that it hosts.
Every day, a random number between 0 and 65535 is generated by the game. If this number matches the last two bytes of the personality value of any of the Pokémon in the party (that is, the remainder when their personality value is divided by 65536), Mirage Island will appear for that day. The number is generated at 0:00 hours every day and it is active for 24 hours. 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 not generate Mirage Island numbers anymore.[citation needed]
Whenever a Mirage Island number is generated, it will not change within the time it is valid, and the player is able to freely move Pokémon from the boxes to the party or vice-versa until the Pokémon that has the same personality value as the island appears. This makes Mirage Island's appearance even rarer than encountering a Shiny Pokémon, although the probability of making it appear increases with the number of Pokémon the player has.
A man in Pacifidlog Town will tell the player whether or not he can see Mirage Island each and every day, thus determining if the player can reach the location.
The island is inhabited by Wynaut which range from level 5 to level 50. It also bears a tree where one Liechi Berry can be picked. This is the best Berry for Pokéblocks, and will produce Gold Pokéblocks.
Location :
Differences :
Mirage Island
same place without the Island
item obtainable :
a Liechi Berry
Pokemon :
*bulbagarden.net image removed* Wynut with a 100% Of encountering rate.
My experience :
Well i haven't got a chance to went there. Cause i didn't even knew how to went there but now i know cause i have found it in PC. Well since i knew it I Have started to search it every time i try to talk the old man but nah... not at all. Though I know that a 50 lvl (Or something) Liechi Berry is obtainable there and the Pokemon Wynaut in a rate of 100% of encountering it. But i didn't get the chance as of now... but I am trying to find it, I always talk with that old man.. just it depend on my luck right ? well maybe someday i'll find it. And whenever I found it i will take the Liechi Berry and give it to My Blaziken as it made a high level PokeBlocks, Maybe a gold Pokeblock right ? and i think i can won many tough Contest with it.