The Kanto starters, along with other starters, can be found and caught in the wild, and three random starters are given out by an NPC.

Mystic Topaz = Mutated Mew

New Type: Psychic/Poison

It is a stronger version of Mew made by humans to drive back the threat of the legendary Zetmaki. Unfortunately, it became prone to getting poisoned.

Weakness: Has a small chance of randomly getting poisoned in battle regardless of health.

Malachite = Mutated Venusaur

The flower on its back has wilted due to the power of Mutation, so every time it uses a physical attack, it has a chance of recoil.

Weakness: Every physical attack has a chance of recoil, which make people focus more on its higher special stat if they think of getting it.

Larimar = Mutated Blastoise

It is always ready to fight no matter the situation. Its Water moves are useless against Fire types, however.

Weakness: Water moves have no effect on Fire types.

Unfortunately, there is a Mutated Charizard because all Kanto starters get representation.

Imperial Topaz = Mutated Charizard

Its hunger provides its energy in its Mutated form, so it must be holding a berry otherwise it will fall asleep.

Weakness: Will fall asleep if not given a berry.

Golden Beryl = Mutated Raichu

It can only land super effective hits in electric terrain. Otherwise, it won't show its true strength.

Weakness: Can only land super effective hits in electric terrain.

Amethyst = Mutated Arbok

Its poison has become ineffective since mutated energy took over, but its strength is unmatched.

Weakness: Cannot poison another Pokemon.

Aragonite = Mutated Zangoose

Due to its hatred for Seviper increasing in this form, it cannot switch out of battle while fighting one.

Weakness: Cannot switch out of battle while fighting Seviper.

Charoite = Mutated Seviper

Its hatred for Zangoose is stronger than everything else in its body. In this form, it will not switch out while fighting one.

Weakness: Can't switch out of battle while fighting Zangoose.

Bloodstone = Mutated Meowscarada

Its strongest move used to be Flower Trick. However, it cannot use the move in this form, so it must opt for other moves.

Weakness: Cannot use Flower Trick.

Fire Agate = Mutated Cinderace

Despite its speed increasing, it seems that it sometimes goes last in battle. Mutated energy could be the cause.

Weakness: Has a 50-50 chance to go last in battle regardless of speed stat.

Lapiz Lazuli = Mutated Swampert

It has no control over its moves. Due to this, it has a habit of using the wrong move when another move is needed most.

Weakness: Sometimes uses a different move from what you picked.

Malaya Garnet = Mutated Tinkaton

After a long time on the battlefield, it seems to get weaker. Respect its wishes and take it out of battle.

Weakness: Every stat decreases by one stage after a long time in battle.

Sodalite = Mutated Lucario

It cannot handle such a massive change in its body. Due to this, it loses health as a consequence for every missed attack.

Weakness: Every time it misses an attack, it loses some health.

Hemimorphite = Mutated Gyarados

Its rage becomes so strong it can only use special attacks, despite its physical stat being much better.

Weakness: Can only use special attacks despite its superior physical stat.

Mali Garnet = Mutated Mimikyu

New Type: Dark/Ghost

It no longer cares what others think in this form and removes its disguise. However, this comes at the cost of its defense.

Weakness: Defense stat is taken from 80 to 60 and Special Defense stat is taken from 105 to 85.

Next:

Part 4: New Pokemon lines that get mutations

Part 5: Legendaries and Regional Mons (Bug, Bird and Mammal)

Part 6: Player Characters, Rivals, and Professor

Part 7: Legendary quartet and mythical