Specifically, the Wits Glamour of the Knights of Avalon, Summon Sidhe on page 216 of the second playtest.
I'm considering making a character with the glamour, but as written, it seems impossibly vague. Not only the core book fails to really describe Seelie or Unseelie in any way, but the glamour itself doesn't give the slightest clue about the strength and abilities of the Sidhe it can summon. What does it mean to have one rank in that glamour? What does it mean to have five ranks? What kinds of Sidhe can you call upon and what are they willing to do for you?