Dandelions

The Dandelions are a group of Keyblade wielders with strong hearts, chosen by Master Ava for the world after the Keyblade War.

Kingdom Hearts χ Back Cover
The Master of Masters assigned Ava with gathering the finest Keyblade wielders, regardless of their Union, so that they can preserve the light after the inevitable Keyblade War. Once the war begins, they're to, like Dandelions, fly away from the warring world. The Master also explained that they would continue the Unions, with only one of them receiving a copy of the Book of Prophecies. He then gave Ava a list of Keyblade wielders to be Union leaders, with the one circled in red meant to receive the Book of Prophecies.

Kingdom Hearts χ
While trying to look for Ephemer in the Foreteller's chamber, Skuld, Chirithy, and a come across one of the Foretellers, who claims to have defeated Ephemer. However, after fighting the Foreteller, the three find out that it is actually Ava who has fought, and that they were never in the Foreteller's chamber. Ava explains her role, and invites both Skuld and the Keyblade wielder to join the Dandelions. While Skuld readily joins the group, the Keyblade wielder chooses to hold back, later explaining that they don't like leaving the others behind.