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For a main banner I would like something with Dusknoir/Gengar/Aegislash/Chandelure, Preferably with Dusknoir and Gengar featured.
If we're also doing sub-banners (Don't need these now, feel free to decline, I'll pay more if you wish), I think for Kanto the two mega-Zards would be nice, Johto would look good with the Legendary Beasts, Hoenn might be nice to have Manectric/Camerupt, Sinnoh could do well with Electivire/Magmortar, I think Braviary/Mandibuzz would be fun for Unova, and Kalos would do well with Trevenant and Gourgeist. Again these are optional and I would pay extra if wished. I look forward to the results :).