All you do is battle your rivel and find:

Charmeleon (Very Rare) 3%
Grovile (Very Rare) 3%
Crawcona (Very Rare) 3%
Bagon (Rare) 6%
Dratini (Rare) 6%
Gible (Rare) 6%
Lavitar (Rare) 6%
Skuropi (Rare) 6%
Swablu (Uncommon) 7%
Horsea (Uncommon) 7%
Ekens (Uncommon) 7%
Aron (Common) 10%
Feebas (Common) 10%
Shinx (Common) 10%
Buneary (Common) 10%