From February 11 to February 14, there is a 20% chance to encounter a Milcery with the Gigantamax factor in any Max Raid Battle. Each of these Milcery have a 100% to drop a Rare candy, and a 30% any one of the 7 types of sweets required to evolve Milcery (This does stack, allowing you to get multiple sweets from one raid). As a bonus, in five-star Max Raids there is a 2% chance that you will encounter a shiny Milcery. For more info visit https://www.serebii.net/swordshield/maxraidbattles/eventden-valentine'sday2021.shtml.