This is a tough game but I enjoyed the sawed off shotgun. Pressing L3 (left analog stick) will let you see danger zones as this can easily backfire to be checkmated (I dont think you can manually capture pieces like a normal king if out of ammo, though I saw a blade power) where you have to move to.
Shotgun King: The Final Checkmate is a roguelike with card buffs as you play as a black King who shoots down white pieces (lol black power), with both sides getting card buffs each round. Don't look up forcefeeding as that can get nasty outside the game (more ammo is helpful).
There are also soul cards that let you move like a knight or bishop, as well as wands that do random damage. Thankful for variance as it would suck to always get owned by iron maiden white queens (they're as indestructible as they are punny).
Wish I could save in game (have easier mode than 3 shells to get other mode unlocks better) or know all the controls, but I guess it teaches to misplay less and time moving reloads (you can't skip consecutive turns to stand and reload).
Plot is kinda funny with black pieces defecting to the white side to get better benefits (black King is a miser and cruel).