Purifying Lugia Easily
First leave several poke snacks in the oasis poke spot and eventully hoppips will appear. Once you have a 36 hoppips put them all in the purifying chamber it does not matter what order you put them in but put 4 in every circle. Put your shadow Lugia in set 5 and it will say something strange is happening to Lugia. Purify it and enjoy your bright colored lugia!
This works because flying is super effective against grass and hoppips are grass flying!
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