If you search in the codes of Ruby & Sapphire, you can find music from Generation 2 (Gold, Silver, Crystal). Known pieces include:
- BGM from Route 38 & 39
- BGM from Pokemon Communication Center
- BGM from Generation 2 Saffron City
- BGM from Crystal’s legendary beasts battles
- Team Rocket’s Theme
Is unknown why these music tracks were put in it. Maybe it was for being able to go to Johto or even Kanto, or just stand-ins.
There was also two beta Pokemons: Shellos & Gastrodon. If you’ve played Pokemon Diamond/Pearl you sure know which these are, and they were actually going to be included in Ruby & Sapphire. Shellos & Gastrodon though were not supposed to look like they did in Diamond/Pearl. This how they were going to look like:

Shellos‘s beta back sprite

Gastrodon‘s beta back sprite
For more infos: Bulbapedia
Leave a Reply