In past games, you can get a shiny charm to increase your chances of getting a shiny. I want to know if you can get it in Pokémon ORAS.
Yes, the Shiny Charm is available in OR/AS, and the method to obtain it is the same as in the previous two games. You must first complete the National Pokédex, and then speak to your game's Professor (Birch, in this case). Completing the Pokédex in this context does not require you to have obtained any of the event distribution only mythical legendaries. You might need to progress the story to the point where the Regional Pokédex is upgraded to include National Pokédex.