Breeding - Rangi42/polishedcrystal GitHub Wiki

Happy breeding!

Notable Mechanics

See also: breeding.asm, daycare.asm; Modifications

  • Egg Groups: Pokémon Learnsets have Egg Group info on each species' page.
  • Egg Moves (egg_moves.asm)
    • The male parent passes them first, then the female.
  • Mr. PKMN will now exchange your Red Scale with a perfect-IV (6IV) Shiny Ditto.
  • Forms are now inheritable. If the parents are the same species with different forms, either of the two will pass its form to their offspring (50% chance each); otherwise the female (or non-Ditto) parent will do. Everstone has no effects on forms.
  • The caught Poké Ball is also inheritable in the same way.
  • The Everstone for passing Nature, the Power items for the corresponding IVs, and the Destiny Knot for five IVs instead of three are all available.
  • The Mirror Herb for Egg Move transfers between the parents is also applicable, but a transfer now occurs with a 1/256 chance for each step by the player while the parents are left in the Day Care.
  • The Ability Capsule is now effective when held by parents. It gives a 25% chance of producing Hidden Ability offspring for each parent holding it.
  • After the Ability Capsule check, the female (or non-Ditto) parent now has a 60% chance of passing its Ability, no matter which Ability it has.
  • The Masuda method is available for Shiny breeding. It's now triggered by a couple of different OTIDs, instead of different languages.*
  • Nidoran-F has an equal chance of having Nidoran-F or Nidoran-M as her offspring.
  • Nidorina and Nidoqueen can now breed as part of the Monster/Field Group.**

* Online features for Polished have been suggested, which may lead to further modification on the in-game Masuda Method.

** Ever since the debut of breeding feature in the canon, Nidoran-F has been able to give birth to both Nidorans while Nidorina and Nidoqueen has belonged to the No Eggs Discovered Group. Nidorina's loss of its breeding capacity was even designed in Gen. I days (or before breeding was a thing), as described in the lore chapter of the Japanese semi-official book Pocket Monster Zukan (1996, Aspect Corp.) — one of the oldest Pokémon guidebooks supervised by Ishihara, co-written by the then Game Freak publication department chief Tomisawa with GF's direct-feed data, and published five weeks after the Japanese Red/Green release.

Efficient Breeding

Spend Ability Capsules/Patches, Bottle Caps, and Mint Leaves wisely.

If you (have to) decide on manual breeding, here's the traditional method, though the Mirror Herb will free you from the Egg Move part:

  1. Groundwork:
    1. Get a Pokémon with Synchronize for each of the good Natures
      • Abra comes in handy at Goldenrod Game Corner
      • You'll at least want Jolly, Timid, Adamant, Modest, Bold, Impish, Calm, and Careful
    2. Get a Pokémon with Flame Body or Magma Armor
    3. Get a parent of the desired Nature with the help of the corresponding Synchronizer
      • If you can't for a reason (e.g. your Starter), consider catching a Ditto of the desired Nature instead
    4. Find out Egg Moves you want and get a male parent who learns the desired moves
  2. Begin breeding while making the most of inheritances, preferably in the following order with the parent(s) to be replaced as needed:
    1. Nature with an Everstone + Egg Moves
    2. Ability
    3. and IVs with a Destiny Knot and a 6IV Ditto (Mr. PKMN's Ditto will also turn on the modded Masuda method for Shiny breeding!)
  3. Hatch Eggs while speeding it up with Flame Body or Magma Armor
  4. Keep breeding with a 4IV parent and the 6IV Ditto

Props to vanilla breeders for the knowledge.