Sideboarding
Sideboarding is the most important and perhaps the most nuanced aspect of piloting Kirin Combo. With access to many of the best sideboard cards in the format, it is very easy to overboard in some matchups without a well thought-out sideboard plan. In addition, to sideboard optimally you need to find the best balance between your midrange and combo plans in every matchup; if you go too far in either direction, the odds are high that you’ll get steamrolled.
With that being said, the list above uses a mix between a toolbox and quasi-transformational sideboard to maximize both elements of the deck. Sounds weird, I know, but let me explain.
In many matchups, you’ll keep the combo core intact and bring in a few tutorable pieces to hedge against whatever your opponent is doing. However, against certain strategies (like discard decks, for example) it’s viable to board out core cards such as Aether Vial or Eladamri's Call
and shift to a more midrange-focused plan. Gavin Verhey calls this the “half-transform”; you adjust your approach to the game while maintaining the threat of the combo. This is why the sideboard isn’t strictly composed of silver bullets like you might see in other toolbox decks—singletons become a lot worse when you remove their accompanying tutor spells.
With this in mind, my rule of thumb is to always keep these cards in your deck: 4 Celestial Kirin, 4 Ugin's Conjurant
, and 2-3 Ranger-Captain of Eos
. More detailed notes on sideboard plans and the theory behind this approach are in the Sideboard Guide below.