The crux of this hack is obviously the inclusion of the Fairy-type at 100%.
Most of the changes were done from a technical standpoint.
These are the few parts of the storyline that were changed as of now:
the girl in Ilex Forest gate that gave you the TM12 now gives you instead the Eviolite.
Several TMs have changed location.
the Day-Care lady gives to you the Odd Egg which can hatch into any 17 non-Togepi babies.
all 16 Gym Leaders first teams got revamped, as well as those of the Elite 4, Lance and Red.
all 16 Gym Leaders second teams got revamped, as well as those of the Elite 4, Lance.
the inclusion of Lv.100 battles against Gym Leaders, Elite 4 and Red after defeating the latter for the first time.
Revamped type-chart to include the Fairy-type matchup as well as all the neutral match-ups.
Pixie Plate implemented.
Roseli Berry implemented.
Fairy-type Arceus in place of ???-type Arceus.
Updated Judgment to take into account the Pixie Plate.
Pokédex fully updated to take into account the Fairy-type in Research mode.
Conversion updated to take into account the Fairy-type.
Conversion 2 updated to take into account all 324 types match-ups.
Battle Hall includes the Fairy-type row.
Pokédex Fairy-type icon.
Shiny lock removed for opponents Pokémon in all 5 facilities.
New items available for purchase.
Battle Frontier Pokémon will always have an IV of 31 inall 6stats.
Battle Frontier Pokémon will always have the ability who is the best tailored for a given set
Battle Frontier Pokémon EV and IV generation has been modified to optimize Hidden Power, Gyro Ball and Trick Room most notably.
Shiny lock removed as well for the NPC partners in Multi Battle mode.
As said earlier, Battle Hall includes the Fairy-type row.
You still fight in rounds of 10 battles.
The SilverPrintis now obtained by challenging and defeating Argenta on the 80th battle.
The GoldPrintis now obtained by challenging and defeating Argenta on the 180th battle.
Other mechanics inherent to the Battle Hall were updated to grant a flawless experience of the facility.
Shiny chance is now 1/4096.
Having a Pokémon with the Ability Super Luck leading the party increases the likelihood of encountering a wild Shiny Pokémon.
Shiny generation from “forced shiny encounters” method was slightly altered to take into account the modified Shiny Rate.
Cute Charm PID generation is improved and no longer restricted, which means you can no longer abuse Cute Charm for easy Shinies.
Shellos and Gastrodon East Sea forms are now available in Kanto.
+50% Physical Defense boost for Ice-types under Hail.
Soundproof check against Heal Bell removed.
Stealth Rock damage is decreased by half.
Fixed the move Hail, basically in gen IV the way Hail is coded allows you to use Hail despite Snow Warning.
Fixed the move Fire Fang so that it doesn’t hit through Wonder Guard anymore unless it happens to be super-effective.
Hidden Power can be Normal or Fairy type now as well, the Hidden Power NPC will notice this too.
Hidden Power no longer takes into account Speed tocalculatethe type.
Some Base Stats were upgraded to help some Pokémon perform better (for example Persian or Probopass).
Starf Berry can now sharply increase accuracy and evasion.
Castform and Cherrim alternate forms now display their respective icon during battles.
Castform’s alternate forms now display their respective type when checked through the menu during battles.
HP bar graphics were changed.
HP are now displayed for the opposing side in single format, double format is unchanged in that regard.
Fixed Strength graphical glitch that also occurs in the original versions.
Fixed Facade graphical glitch that also occurs in the original versions.
Battle Style is now permanently locked on Set.
You can’t use items from your bag against a Trainer, very much like against Battle Frontier Trainers!
All Trainers’ Pokémon have now 31 IVs inall 6stats.
All Trainers’ Pokémon have now 255 EVs inall 6stats.
All Trainers’ Pokémon have now the possibility to easily get beneficial natures.
All Trainers’ Pokémon have now the possibility to be shiny.
IVs for opponents’ Pokémon can be chosen from a pool of 64 combinations, most notably to capitalize on Hidden Power, Gyro Ball and Trick Room.
All Trainers’ Pokémon can now be contained in Balls other than Poké Balls.
The number of possible seals combinations for opponents’ Pokémon went up from 28 to 216.
Ace Trainer Lois replaces Juggler Irwin in the Pokégear, you can set a rematch with her on Wednesday afternoons (10:00 to 19:59).
ASM hack to allow more than 737 trainers in-game (complete with text).
Continuity for opposing Trainers is preserved, by that I mean that the IVs, nature, shininess and gender of opposing Pokémon stay the same (for example Falkner’s Pidgeot is canonically the same creature as when he was only a Pidgey).
Alternate Forms from Trainers now have their correct Ability as well as the correct Base Stats’ spread.
A new item was created, the Evolutor, which when applied like an Evolutionary Stone to a Lv 100 Pokémon, allows it to evolve if it can do so!
Eevee can now evolve into Leafeon if leveled-up at Ilex Forest or Viridian Forest.
Eevee can now evolve into Glaceon if leveled-up at Ice Path or Seafoam Islands.
Magneton and Nosepass can now evolve into Magnezone and Probopass respectively if leveled-up at Team Rocket HQ, Route 10 or Power Plant.
Feebas, on top of requiring a beauty’s stat of 170 min, is now required to level-up at least at level 20 to be able to evolve.
Feebas gains a second failsafe evolution method in case the Sheen is maxed before the Beauty stat reaches 170.
Female/Male Kirlia evolves into Gardevoir/Gallade at Lv 30.
Female/Male Snorunt evolves into Froslass/Glalie at Lv 42.
Female/Male Clamperl evolves into Gorebyss/Huntail with the Dawn Stone.
Evolution methods 0xB and 0xC (Wurmple) were changed to make a Pokémon evolve by level-up at day (Silcoon) and at night (Cascoon) respectively, because making an evolution method based on the PID of a Pokémon is quite frankly a bad design.
Pokémon that require a trade to evolve all gained an alternate method of evolution.
Incenses babies are now the default base form.
Miltank and Tauros are now considered the same species for breeding purposes.
Feebas/Milotic and Magikarp/Gyarados are now considered the same species for breeding purposes.
Females can now pass egg moves as well, eliminating all impossible egg moves combinations.
A new NPC, called the Egg Move Tutor, makes an appearance; as the name implies he is capable of teaching your Pokémon moves that normally it has to know from birth, but also level-up moves that only pre-evolutions can learn, and for some Pokémon moves that they have no other way to learn, but you’ll have to spend 100 BP to pay for his services!
The Odd Egg will be given to you by the Day-Care lady!
Gender ratios are fixed, with that I mean that for example 1 male per female REALLY means 1 male per female (and not 129 males for 127 females).
Ponyta, Rapidash, Gardevoir, Feebas, Milotic and Gorebyss are now female-only.
Magikarp, Gyarados, Glalie and Huntail are now male-only.
EV limit is now 1530, you can max all stats now.
The new EV limit also applies in the Battle Frontier.
Vitamins cap at 255 EVs now.
Vitamins give 15 EVs per usage now.
Lv 100 Pokémon can gain EVs by fighting now, but they still need to be deposited in the PC for the stat gains to take fully effect.
IVs no longer have an effect on stats, that is stats are always calculated assuming an IV of 31, this is done to not disavantage you to much against Trainers, especially early-game.
Pichu and Raichu benefit from Light Ball as well now.
TM45 and TM78, which contain Attract and Captivate respectively, have been updated with a Fairy-type TM icon.
TMs are now reusable.
you can no longer throw away TMs.
you can no longer give TMs to hold.
Purchasable TMs, regardless of the currency, can only be bought one at time and only once.
TM56, TM86 and TM26 are no longer Pickup items and were replaced with Lucky Egg, Life Orb and PP Max respectively.
each of the 92 TMs is available only once!
If possible, moves were upgraded to match Gen V+ information.
Nerfs from Gen VI are NOT applied (this means that for example Surf and Hydro Pump remain at 95 and 120 power respectively).
Even moves like Tail Glow, which should boost the Special Attack by 3 stages, have been updated successfully (complete with the text).
Acupressure now works if the user is behind a substitute.
Sleep Talk can now be used multiple times under the effect of Choice Items and/or Encore.
SFX for some moves were altered to suit them better.