So, here's the sitch. GameFreak won't stop popping up worthless alternate forms. So instead of a massive sludge of gimmicks, this allows for the creation of a form family for each species, and it will allow for a form system that allows for feedback to the originals, which is something Megas only briefly bothered with. It also to helps to satisfy GF's and fandoms desire to redesign everything ever to be more hip, cool and narly.
So effectively, I'm suggesting that each Pokémon should have (at least) four type combinations, each separated to a tier of their own. These tiers are separated in terms of their relation to original as well as their expected gameplay superiority and rarity. The tier 4 is the farthest from the original Pokémon, while the tier 1 is original typing. Each tier is visually distinct from each other, with Tier 4 being the most distinct from Tier 1. Most tiers also have different stats from each other, while keeping the same BST and HP, much like any other alternate form.
Tier 1= Original Pokémon:
Basically, the original typing of the Pokémon would be now retconned into the basic form of the species. These would be the forms you get the Pokémon in most basic routes, and early gifts. Obviously, the starters and legendaries would be initially also available at this tier.
The fact that this is the most common tier on average doesn't necessarily mean it will be the default form you will encounter in all areas. As the type changes grant Pokémon different capabilities that will ensure their survival in other areas, certain areas might exclusively contain other tiers as uncommon or rare encounters for most Pokémon, and common encounters for early-game Pokémon. However, distribution of these would be obviously limited compared to the originals.
Tier 2= The primary non-elemental implied typing:
Tier 2 would be more varied in terms of its approach compared to tiers. Tier 2's goal would be to expand the original idea over everything else. However, the exact method would vary depending on the species' type. In addition, the Tier 2 would be the second most common tier and the variety that is available mostly in wild, as such this tier cannot provide high tier non-elemental types such as Dragon, Ghost or Fairy, or high tier elemental types such as Fire, Ice or Electric. Instead, this tier will focus on readjusting existing dual types and granting single types their implied lower tier non-elemental types, such as Normal and Dark, and less specialty requiring types such as Ground and Water.
In addition to this, this tier also provides original typings of Pokémon back to canon. Such as pure-Electric Magnemite family and pure Normal Clefairy.
Since no legendary would be as common enough to have four different variations, hence why none of them have more than to abilities, for legendaries this would be their answer to Tier 4.
a.Readjusting existing types:
Basically, here's how it goes. Almost all of the recent Pokémon that are dual typed come from a single typed Pokémon. For most of the time, this is just a worthless gimmick that ensures moveset superiority of the fully evolved Pokémon over others, and has little in-game reasoning. It is also used as a cheap means of keeping suspense for the pre-release period, as the only reason starters and several pre-release Pokémon don't have dual types is to keep the mystery going. On the cases it has in-game reasoning, it still doesn't explain the lower moveset of the base original. The type readjustment does away with that nonsense, mostly.
Fennekin Tier 2 would now Fire/Psychic at start, and Fletchling Tier 2 would be now Fire/Flying at start.
Fennekin Tier 2 can have Future Sight and Extrasensory, but it cannot learn Fire Blast and Flame Charge through Level-Up like Fennekin Tier 1.
These new moves, at least most of them, would be available to most tiers either as Move Tutors, TMs or Egg Moves. Similarly, most of the lost moves would be accessible through the same method. Thus, the Pokémon would enjoy having the moveset of two different species, without actually being two different species molded into one.
The inverse would be true, especially for those who have noticeably different types for sake of type variety or older design conventions. For example;
Drapion Tier 2 would be now Poison/Bug to preserve the unique typing, even if the type combination isn't necessarily unique.
Geodude would be pure Rock-type, as Rock/Ground is no longer the default form for Rock-types.
These cases would be primarily to increase the moves of the entire form family as many dual type Pokémon simply lack the access to a variety of their original types' moves. In other cases, it would be to be consistent with type expertises of the Gym Leaders and Elite Four.
b.Using implied types:
This would be primarily used for single typers, but certain dual types whose implied typing would be inferior to original such as Venomoth's Bug/Flying would also get these as their Tier 2 variant. As Tier 2 Pokémon can't be especially great, most of the implied typings that would be used would the said lesser elemental and non-elemental types. For example;
Charmender-line's true implied alternate type is Dragon-type. However, Dragon-type is far too powerful and elusive type to be used liberally. And both Flying and Rock-types don't make sense for its initial anatomy, and Fire/Ground is too powerful offensively with Charmender's stats. As such, Charmender's Tier 2 typing would be Fire/Dark instead, as Dark-type is one of Charmender's implied typings.
Tier 3=The primary elemental implied typing:
Of course, as we said before, Pokémon have more than one implied typing. In fact, certain types such as Ground has Rock, Steel and Fighting as its implied typings, regardless of the species. As such, a less common but still common enough tier should be utilized for more middle-of-the-road but still good types such as Fighting, and more specialized types such as Poison, Rock and elemental types such as Fire and Electric. However, Steel, Ghost, Dragon and Fairy are still way too good to give away casually. But for certain Pokémon such as Milotic who has Dragon AND Fairy as its implied types, one of them has to be given away at this tier.
This tier also allows for Pokémon who didn't gain their implied typing in the previous tier to gain their typing here, such as Jigglypuff who got pure Normal in the previous Tier can gain Dark/Fairy in this tier.
This tier is much more free than previous tier, as such this tier would be more prone to exclusive moves compared to Tier 2. Otherwise, this tier remains the same as the previous one.
Tier 4- Elusive typings:
This tier would be the rarest of them all, and the most distant from the original. Basically, this is the last tier that contains implied typings. This is not an "anything goes" space, however. The types that are presented are still logical in terms of their original design and/or dex description, but they are not always consistent with the movepools or competitive usability. For example;
Beautifly's Tier 4 typing is Bug/Dark. This isn't because of its movepool, but rather its Ability Rivalry and its dex description, which states that it is an aggressive Pokémon. As such, it is a Tier 4 typing because type-wise it is farthest away from its original.
However, even if this tier contains specific moves to itself more so that previous tiers, any TM, Move Tutor and Egg Move changes given to it are also given to all other tiers. Similarly, a large section of its exclusive content is still available to other tiers, when it is possible to distribute them.
Most of the starters' Tier 4 typings would presumably be either available post-game, or event-exclusive. That's assuming the alternate types aren't given special breeding mechanics.
Now the initial proposal is over, let's go over with the Q&A and then the Appendix:
How this will effect the Dex?:
The same way any forms do. The form you first encounter will be the one listed, but only the primary will be listed outside of searching. When searching, you will be able to search for the specific typing you want.
How will the breeding mechanics work?:
Same as with other forms, the female's form is the one that determines the baby.
How will the Mega Evolutions work?:
Each tier will have its own separate Mega Evolution, with different stats and types. Their abilities will remain the same. Fire/Dragon's Mega Charizard X will be Fire/Flying, for example.
How will the movesets and stat distributions work?:
Movesets will be the same as the originals, but with different moves and arranged differently. In other words, it will be similar to counterpart Pokémon like Plusle/Minun, but with more differences at levels when the same moves are learned.
The stat distribution will be the same as any other form. Same HP and BST, but different distributions to better fit the type and design.
How will existing Form Changes work?:
Just like how all Megas will be different, so will the form changes. Alternate Forecast Forms of Castform will have different secondary typings, and cosmetic forms will have different designs to fit new bases.
The forms that don't have type changes, such as the legendary Formes, will keep their base's type, whatever that may be. Rotom's alternate formes will keep their types, but might have slightly different stats depending on the base.
Other type changes such as Protean are dual-type agnostic, so they are not important to discuss, unless their mechanics are changed.
Mutation, or, How to gain Alternate Types without searching?:
As means of getting Alternate Types without searching, I propose the Mutation mechanic, inspired by the Mutation mechanic in berries. Effectively;
Breeding a Pokémon with the alternate type the female grants a chance of giving a baby with the alternate type. Ditto doesn't count. If the male parent is the desired Tier, the chances double.
The exact percantage depends on the Tier. The speculative percantages would be;
- Tier 1 Pokémon can only produce a Tier 4 Pokémon with %5 chance, a Tier 3 Pokémon with %20 chance, and a Tier 2 Pokémon with %40 chance.
- Tier 2 Pokémon can produce a Tier 1 Pokémon with %30 chance, a Tier 3 Pokémon with %30 chance and a Tier 4 Pokémon with %10 chance.
- Tier 3 Pokémon can produce a Tier 1 Pokémon with %30 chance, a Tier 2 Pokémon with %30 chance and a Tier 4 Pokémon with %10 chance.
- Tier 4 Pokémon can produce a Tier 1 Pokémon with %10 chance, a Tier 2 Pokémon with %20 chance and a Tier 3 Pokémon with %40 chance.
Male and Genderless Pokémon achieve mutation through holding specific items for producing each tier when breeding with Ditto. The percantages are the same as the female without the desired Male as parent.
Other potential tiers:
Tier 3.5 = Remaining implied types:
As discussed before, most Pokémon have a fair amount of common implied types. So additional tiers can be added to accommodate for them. Unfortunately, not all species have this kind of flexibility, but it is something to consider.
Tier 5 = Extreme diversion or Delta Species:
The goal of this tier would be to take the species as far away from the original, purely for the lulz. This would require very careful planning to not change balances, because the purpose of these tiers are to expand on the existing Pokémon. So such a tier would have to find a balance of being distinct enough while granting wider access of tiers and not break the game.