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The problem is I have no experience using Cresselia apart from AceStarThe3rd's semi-stall and my first attempt at a balance team which I only used about five times.
*hint*
i only have a bit experience with alakazam (havent used revenge killer set, lo set only a few times), and clefable ive only used unaware+cm, cm+mg, unaware wall sets lol
but i do have tons with kingdra+latios