The requirements were also confirmed on the Portal update: participate in the event, which in past years has simply meant finding at least one negg on one day. (Then returning to the hub to receive your final prizes.)

This year's Festival of Neggs has launched, with a grey Kari once again!
For a full rundown of where to go (if you want to skip the hunting yourself), check out our guide for solutions:
As is usual for this event, the first day is advertised as "day 1.5" and will run through the end of April 11th. You will then be able to hunt for the second negg starting on Saturday, April 12th.