This is a Wild Area event held by Sword and Shield. This event does not appear to host any Gigantamaxes.
This raid gives players a chance to land on a slot with a guaranteed shiny Eiscue, 2% chance at 5 star raids.
Every slot gives players an encounter with Eiscue, to commemorate the World Penguin Day.
To import these files into your save, use PKHeX's block importing function. Our tutorial should guide you through it.
Our first post of this page contains some data relevant to the importing stage.
There's info and some common questions regarding Wild Area Events here.
To see other Wild Area Events, here.