The Rock Trade-In is where you can trade in the rocks you obtain randomly through searching in Legendary Area in exchange for Pokemon. These rocks are also obtainable in the Mines. There are 10 types of rocks: Green, Blue, Orange, Yellow, Pink, Red, Gray, White, Cyan, and Purple.
The Pokemon received depends on the total amount of rocks that are traded, in which the colors do not seem to matter much, if anything. These amounts do seem to be set, however most of the time there will be at least 2 different Pokemon obtainable with this amount and thus will still be partial to luck. Generally, the more rocks that you blend, the rarer the Pokemon received will be. Supposedly there is a cap at 20,000 rocks, however this has yet to be confirmed.
List of Obtainable Pokemon Edit
Some of these are estimations, though guaranteed to work. More information has yet to be discovered as to what the specific amounts are for these transitions.
|Total amount of rocks||Pokemon obtainable #1||Pokemon obtainable #2|
|26-35||Shiny Spoink||Ruby Meowth|
|36-55||Emerald Spoink||Crystal Meowth|
|56-130||Ruby Spoink||Emerald Meowth|
|131-205||Dark Spoink||Golden Meowth|
|217-231||Shiny Paras||Ruby Squirtle|
|232-300||Emerald Paras||Crystal Squirtle|
|310-380||Ruby Sandshrew||Shiny Gastly|
|540-600||Emerald Snubbull||Dark Cyndaquil|
|610-680||Dark Snubbull||Shiny Cyndaquil|
|685-750||Ruby Snubbull||Emerald Cyndaquil|
|840-990||Shiny Burmy||Golden Cyndaquil|
|1,000-1,350||Emerald Burmy||Silver Cyndaquil|
|20,000||Crystal Groudon||Dark Entei|