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Rayquaza Weekend PSA
In case anyone is anticipating shiny Ray, it's been verified by a couple East Asian Twitters and from TSR mods on Reddit that Rayquaza will NOT be shiny the weekend of the 15th. It's just a return for people to flex their Swinub day gains.
Carry on.
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At the same time, given that shiny Kyogre has been available for extended periods of time twice and Groudon for one extended period, it would be a bit of a letdown that shiny Ray was only available for one weekend in winter.
I think they realize it would probably generate more interest (and cash for them) to wait for better weather and do a 3-hour Rayquaza day where shinies are available.