Assuming it´s him let´s guess his ability. This we know about him: "Despite elves typically not finding humans to be attractive, he was secretly in love with Yennefer, though he never revealed his feelings to the sorceress".
What I would assume is a payoff card getting an advantage dependent on the total amount of different allied elf mages or played SC spells.
Please find attached my example.
"the author of the first correct solution will receive a piece of a different kind of puzzle, provided by Ryan, to post here on r/gwent. EDIT: Congrats to /u/AltMarina! Artwork piece can be seen here."
This "reveal campain" is way too slow! There's supposed to be 12 new cards, so they could release at least 5 puzzle pieces every day - leak all the arts and leave abilities and patch notes for Masters.