Why cant Aggron learn Head Smash in Pokemon Platinum?

Head Smah is an egg move on Aggron which was introduced in GEN-4 but it is said it is not compatible to get Head Smash in Pokemon platinum.Ther is a Pokemon which can learn Head Smash in Pokemon platinum and in the egg group of Aggron(i.e) Rampardos but why cant I get it.I left a female Aggron and male Rampardos Knowing Head Smash in the day care centre will I get a Aron with Head Smash.If yes Ill wait for the to breed.If no I want to know why is this not possible.

Pleaselog inorregisterto add a comment.

Egg moves are based on individual games, not the generation. This is why the same exact egg move and Pokemon can be compatible in HGSS, but not DPP, even though they’re both gen 4.

If you really want an Aggron with Head Smash in DPP, you’re going to have to breed an Aron with Head Smash in HGSS and then transfer it to DPP via pal pad.

Basically, don’t bother trying to breed it with Head Smash in DPP. It won’t work.

If this is what you mean, Aggron can’t learn Head Smash in Diamond and Pearl or Platinum. It learns it as an egg move in HeartGold/SoulSilver by breeding with a Rampardos or Nidoking.

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