Note: Here are the skills that Kalin Kessler possibly acquires or used in event.
Return 1 to 3 cards from your hand to your Deck. Then, apply 1 of the following effects, depending on the number of cards you returned. This Skill can only be used once per Duel. ● 1 Card:Place 1 "Infernity Archfiend" on top of your Deck from outside of your Deck. ● 2 Cards: Play 1 "Infernity Necromancer" from outside of your Deck. ● 3 Cards: Play 1 "Infernity Launcher" face-up from outside of your Deck.
We probably won't see those archfiend since they are a little OP, mind you. But that doesn't mean we would never get even a single copy of each of them, just wait... They probably will released them at next event, or badly, in the next boxes
The synergy is fantastic; I hope we get more Skills like this one in the future.