Sprocket
P(n) = 1 - (1 - P(1))^n
The Breeding Guide has proven to be very useful for my breeding efforts. However there's a few quirks in it that don't seem to apply in HeartGold and SoulSilver. Here's a small list of those quirks and their corrections as they relate to HG/SS:
Part 1 - Section 2 - The Battle Frontier IV Guy
In HG and SS you can find the IV guy in the Battle Frontier's Battle Tower, which opens up after receiving the National Pokedex. He's at the far upper right of the Tower, next to the glass elevator thingy.
Part 1 - Section 2 - WiFi Battles
WiFi battles are also possible in HG/SS and Platinum.
Part 1 - Section 2 - Pokemon Characteristics
Pokemon Characteristics are part of HG/SS as well as Platinum.
Part 1 - Section 3 - How the game provides IVs to an egg
HG/SS uses the R/S/FR/LG method for IV distribution.
Part 1 - Section 3 - Power Items
A new mechanic in HG/SS is the ability to choose which IVs to pass down using the Power items (which are bought in the Battle Frontier). Whichever parent is wearing the Power item will pass down their IV to the offspring (ie: a Male Pokemon wearing a Power Anklet will always pass down its Speed IV, even if bred with a Ditto).
If both parents are wearing a Power item, the game will randomly choose which parent passes down their IV via the Power item For example, if a Male pokemon wears the Power Anklet, and a Female wears the Power Band, you have a 50% chance of guaranteeing the Male's Speed is passed down, and a 50% chance of guaranteeing the Female's Special Defense is passed down. There is still a chance that you will pass down both the Male and Female IVs anyway; the Power items just guarantee one or the other will be passed down.
(further research is required to determine how many more IVs are passed down when using the Power items. Near as I can tell, using a Power item guarantees the chosen IV is passed down, with two more from either parent being passed down at random, with the remaining 3 randomly generated).
The Power items are as follows.
Power Anklet - Passes down Speed
Power Band - Passes down Special Defense
Power Belt - Passes down Defense
Power Bracer - Passes down Attack
Power Lens - Passes down Special Attack
Power Weight - Passes down HP
Part 2 - Section 1 - Magma Armor / Flame Body
In HG and SS, you can find the Pokemon with these effects at these locations:
Magby - Pokewalker (Rugged Road, Amity Meadow)
Magmar - Burned Tower and Safari Zone (Peak area)
Slugma - Route 16, 17, 18, and Pokewalker (Volcano Path)
Part 2 - Section 1 - Everstone
In HeartGold and SoulSilver, the Everstone works by passing down the nature of whoever holds the Everstone, regardless of Gender or Ditto usage. If both parents hold an Everstone, you have a roughly equal chance of passing down the first parent's nature, the second parent's nature, or generating a random nature.
Both parents need to have the same owner for this to work. Otherwise the Everstone will fail.
Part 2 - Section 1 - Ditto
Abras are very available in HG/SS. You can find them in Routes 5, 6, 8, 24, 25, 34, 35, the Safari Zone, the Pokewalker (Town Outskirts), and as a Goldenrod Game Corner prize for 200 coin.
Wild Dittos are found in routes 34, 35, 47, the Cerulean Cave, and the Safari Zone. I've had the best luck with Dittos in Route 47 (requires Surf and Waterfall to reach). Dittos will also occasionally swarm in Route 47.
The Magikarp technique works flawlessly, but Repeat Balls in HG/SS are fairly rare. Ultra Balls work almost as well, though occasionally you will need to throw two UBs (and rarely three UBs). You could also try Net Balls and Dusk Balls (at night).
Part 2 - Section 1 - Level 5 Stats
This chart doesn't work so well for HG/SS, because Pokemon are born at level 1 and not level 5. However near as far as I can tell, beneficial natures and negative natures still seem to follow the +/- 1 stat rule.
Part 2 - Section 2 - Day Care Location
For HG/SS, the Day Care is found in Route 34, just south of Goldenrod City.
Part 2 - Section 2 - Breeding Roads
In HG/SS, you can either use Route 17, which requires either Fly or the Magnetic Train to reach, or you can run between Route 34 and the north end of Goldenrod.
From the water edge near the old man to the north end of Goldenrod (next to the gate), it's exactly 85 steps. Which is convenient because every round trip and a half is approximately one egg cycle (to be precise it's 255 out of the necessary 256).
Part 3 & Part 4
Near as I can tell, no change to these are really necessary for HG/SS compatibility.
Part 1 - Section 2 - The Battle Frontier IV Guy
In HG and SS you can find the IV guy in the Battle Frontier's Battle Tower, which opens up after receiving the National Pokedex. He's at the far upper right of the Tower, next to the glass elevator thingy.
Part 1 - Section 2 - WiFi Battles
WiFi battles are also possible in HG/SS and Platinum.
Part 1 - Section 2 - Pokemon Characteristics
Pokemon Characteristics are part of HG/SS as well as Platinum.
Part 1 - Section 3 - How the game provides IVs to an egg
HG/SS uses the R/S/FR/LG method for IV distribution.
Part 1 - Section 3 - Power Items
A new mechanic in HG/SS is the ability to choose which IVs to pass down using the Power items (which are bought in the Battle Frontier). Whichever parent is wearing the Power item will pass down their IV to the offspring (ie: a Male Pokemon wearing a Power Anklet will always pass down its Speed IV, even if bred with a Ditto).
If both parents are wearing a Power item, the game will randomly choose which parent passes down their IV via the Power item For example, if a Male pokemon wears the Power Anklet, and a Female wears the Power Band, you have a 50% chance of guaranteeing the Male's Speed is passed down, and a 50% chance of guaranteeing the Female's Special Defense is passed down. There is still a chance that you will pass down both the Male and Female IVs anyway; the Power items just guarantee one or the other will be passed down.
(further research is required to determine how many more IVs are passed down when using the Power items. Near as I can tell, using a Power item guarantees the chosen IV is passed down, with two more from either parent being passed down at random, with the remaining 3 randomly generated).
The Power items are as follows.
Power Anklet - Passes down Speed
Power Band - Passes down Special Defense
Power Belt - Passes down Defense
Power Bracer - Passes down Attack
Power Lens - Passes down Special Attack
Power Weight - Passes down HP
Part 2 - Section 1 - Magma Armor / Flame Body
In HG and SS, you can find the Pokemon with these effects at these locations:
Magby - Pokewalker (Rugged Road, Amity Meadow)
Magmar - Burned Tower and Safari Zone (Peak area)
Slugma - Route 16, 17, 18, and Pokewalker (Volcano Path)
Part 2 - Section 1 - Everstone
In HeartGold and SoulSilver, the Everstone works by passing down the nature of whoever holds the Everstone, regardless of Gender or Ditto usage. If both parents hold an Everstone, you have a roughly equal chance of passing down the first parent's nature, the second parent's nature, or generating a random nature.
Both parents need to have the same owner for this to work. Otherwise the Everstone will fail.
Part 2 - Section 1 - Ditto
Abras are very available in HG/SS. You can find them in Routes 5, 6, 8, 24, 25, 34, 35, the Safari Zone, the Pokewalker (Town Outskirts), and as a Goldenrod Game Corner prize for 200 coin.
Wild Dittos are found in routes 34, 35, 47, the Cerulean Cave, and the Safari Zone. I've had the best luck with Dittos in Route 47 (requires Surf and Waterfall to reach). Dittos will also occasionally swarm in Route 47.
The Magikarp technique works flawlessly, but Repeat Balls in HG/SS are fairly rare. Ultra Balls work almost as well, though occasionally you will need to throw two UBs (and rarely three UBs). You could also try Net Balls and Dusk Balls (at night).
Part 2 - Section 1 - Level 5 Stats
This chart doesn't work so well for HG/SS, because Pokemon are born at level 1 and not level 5. However near as far as I can tell, beneficial natures and negative natures still seem to follow the +/- 1 stat rule.
Part 2 - Section 2 - Day Care Location
For HG/SS, the Day Care is found in Route 34, just south of Goldenrod City.
Part 2 - Section 2 - Breeding Roads
In HG/SS, you can either use Route 17, which requires either Fly or the Magnetic Train to reach, or you can run between Route 34 and the north end of Goldenrod.
From the water edge near the old man to the north end of Goldenrod (next to the gate), it's exactly 85 steps. Which is convenient because every round trip and a half is approximately one egg cycle (to be precise it's 255 out of the necessary 256).
Part 3 & Part 4
Near as I can tell, no change to these are really necessary for HG/SS compatibility.