Question: pokemon ultra sun and moon how to get genesect?
Answer: Get a shiny Pokemon you HATE (for me, I used Relicanth) and get it up to lvl 100 if you haven't already.
Put that shiny into the GTS and ask for any mythical (for me, I used Meloetta)
Wait awhile and your mythical should arrive! The wait time should be around 10 hours to a day, but no more than 3 days.