Pokémon Rutile Ruby and Star Sapphire are romhacks of Pokémon Omega Ruby and Alpha Sapphire. Their main purpose is to provide a more challenging game experience while not artificially limiting the player. Every trainer in the game has been edited, and the level curve expects use of the Experience Share, which means that you level up very quickly. You should be hitting Level 100 by the time you get to the Elite Four.
Harsher Level Curve: Balanced to the EXP Share
New Trainer teams, many featuring six Pokémon! Even the rematches have been edited!
All enemy Pokémon have max IVs!
All Gym Leaders have six Pokémon!
Trainers throughout the game have access to Mega Evolution!
Alternate Battle Types are more common in the world!
Wild Pokémon Changes
Post-game Foreign Pokémon are avalible from the beginning of the game!
Rarity within areas adjusted
Hordes optimized for painless and early EV training!
Lots more Wild Hold Items!
Everything caught in these hacks is 100 % legit for trade!
Less useless junk in Poké Marts!
Sarcred Asah available in addition to Revive. Revives costs much more, to discourage their use in battle (Sacred Ash is unusable during battle).
Competitive consumables are available in standard Poké Marts!
Slateport Market is now the go-to place to purchase competitive items like Leftlovers and Life Orbs.
Trade Evolutions now have alternate methods. You can still evolve them through normal trade methods.
Eggs now hatch incredibly quickly. Every species now has a 1-cycle hatch rate. Note that Event eggs (Lavaridge Town) glitch out thanks to this, and wrap around to taking a very long time.
Level 3 of the Hatching, Experience Gain, Friendship, and Mony Gain O-Powers now last much longer
Brendan and May have new outfits/designs.
Banners, Icons, and the Title Screens have been edited.