Quoted By:
Hello 4chan, I work for Game Freak and I helped develop the coding for the Omega Ruby and Alpha Sapphire demo. I work on a team that is no part in developing the full game, and was working separately to develop the demo, apart from the team that is still developing the full game.
I'll start with what most of you probably want to hear. The removed Mega Evolutions were Flygon, Zangoose, Seviper, Slaking, Milotic, Butterfree, Ledian, Regigigas, Xatu, Sandslash, Krookodile, Bisharp, Mandibuzz, and Braviary. Game Freak executives were aware of data mining in video games, so I guess they wanted us to hide their biggest surprises.
The Battle Frontier is also returning, and is featuring the Pokémon World Tournament. Also, you have actually battle against Scott, the owner of the Battle Frontier, to advance the story. This is near the end of the game, and his signature Pokémon is a Mega Slowbro.
The last thing we removed was Team Magma/Aqua sidequests at the end of the game, with battles against admins from the two teams and even a battle with Team Flare grunts. We removed this because they use some of the hidden mega evolving Pokémon.
So like I said, Game Freak is trying to keep as much of the full game they are developing as secret as possible. If they added anything new or took anything from what we coded, I am completely unaware. If I hear anything new or something changes, I will come back as soon as possible.