>>50233020DEF, and 50/50 chance of SPC, (either plus or minus 8 points), is always passed on to the offspring of a ditto. So, you catch a Ditto with 15 DVs in DEF, and either 8 or 15 DVs in SPC. Then with enough patience, you eventually breed a Pokémon with 15 DVs in every stat. (ATK and SPD are always random, and HP is determined by the DVs of other stats.) The odds are somewhere around 1 in 500. I bred for Magikarp, because their eggs hast the quickest, and got mine within a day or two of hatching. (You also find some useful Hidden Power types along the way. I found HP Ground at some point.) Then thanks to Stadium 2, you can clone those perfect DVs, as well as any stat experiance onto another Pokémon of your choice.