Kaito has a passive ability that lets you add loyalty counters to him anytime a creature you control deals combat damage to another player, letting you hit that -9 final ability faster
But given that Thousand Moons Smithy comes down and makes a Karn-struct thats reasonably large right away in an affinity deck and then also likely flips the next turn, this seems like a nice artifacts top end, especially because Barracks of the Thousand is an artifact land
For a more detailed look at Connellys art and method, he was interviewed earlier this year and that chat can be found here
Excalibur II BPhillipYork: Charge counters making a creature big is solid
That's pretty common with many great legendary equipment in your colors like Sword of the Animist, Godsend, Mithril Coat, or Embercleave
That is always an opportunity to blow them out with a protection spell from hand