Pokemon Sword and Shield is giving away several Evolutionary items, including the item you need to evolve the game's hardest-to-find Pokemon. Earlier this week, Pokemon Sword and Shield launched another Mystery Gift giveaway to help fans prepare for the upcoming Isle of Armor DLC. This new bundle comes with a Galarian Corsola with the Hidden Ability Cursed Body, as well as multiple Evolutionary Items. In addition to the Sweet Apple, Tart Apple, Whipped Dream and Sachet, the bundle also comes with the Chipped Pot and Cracked Pot, which can be used to evolve Sinistea into Polteageist.
Sinistea is one of Pokemon Sword and Shield's stranger Pokemon, a Ghost-type Pokemon that lives inside a teacup. It also has a secret secondary form, one that can only be evolved using the Chipped Pot. Most Sinistea are "Phony Form" Sinistea that live in counterfeit teacups. However, occasionally Sinistea will live in a genuine teacup, which is known as its Antique Form. You can only identify a Antique Form Sinistea by the authenticity label on its underside, which is usually only visible when it Dynamaxes. It's unclear what the ratio is between Phony Form Sinistea and Antique Form Sinistea, but it's thought to be about 1 in 100.
The other easy way to tell that you have an Antique Form Sinistea is if it can't evolve using the relatively common-to-find Cracked Pot. If your Sinistea won't evolve using the Cracked Pot, then you need the Chipped Pot, which is the "genuine" teapot it needs to evolve into Polteageist.
Keep in mind that there are no stat differences between the Phony Form and Antique Form Sinistea and Polteageist. However, if you're a completionist, you'll want both versions. Unfortunately, the Mystery Gift doesn't come with the rare Antique Form Sinistea, so you'll have to keep hunting for it in the Glimwood Tangle.
Pokemon Sword and Shield's current Mystery Gift promotion runs through June 11th.