if I buy any mythical codes like for Pokemon oras like from amazon will it still give me a mythical Pokemon or is it expired wither I buy it now or not? they have them listed on amazon still but don't wanna waste my money
If it's past the date that the event was going on for, the code won't work.
However, the Magearna QR Code thing is never-ending, so could look up the QR code for your country and do that whenever.
Source: Experience.
