I learned this the hard way years ago when my first Dragon deck looked powerful on paper, but stalled every game because the commander did not support the tribe properly
Kenrith, the Returned King If Queen Marchesa is a good commander for a theme deck around knights, then Kenrith, the Returned King is the perfect commander for it
Its cheap cost makes it powerful, but its sorcery speed leaves the tutored card vulnerable to mill or shuffle effects before you have an opportunity to draw it
Juggernauts matter isnt really a thing, so Graaz is best built around a supporting cast of cheap, scampy creature tokens like servos, thopters, and myr
If an ability triggers "whenever you tap" something for mana and produces mana, that triggered mana ability won't be affected by Nyxbloom Ancient
Reckless Charge is one of the best options since it gives our creatures haste, +3 damage, and it has flashback