While many mega Pokemon have been introduced over the years, Primal Pokemon remain elusive. It is possible they might make an appearance in the next season. The trailer included in this article suggests that they might. Primal Groudon, Primal Kyogre and Mega-Pokemon are both slightly different than the Mega-Pokemon but they are very similar. These are temporary and better forms of Groudon or Kyogre.
We may hear something tomorrow, but we are just guessing.
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