If you only play Commander, then grabbing all five is a surefire way to keep you busy
In fact, outside some infinite combos that instantaneously mill libraries, it's actually quite hard to win in Commander via mill
Given the relatively small amount of removal in Kamigawa: Neon Dynasty limited, there is less risk of this getting one of the player's lands targeted by a kill spell
Common Omnath builds include multicolor matters, 5-color good stuff, or a devotion route with black devotion a particularly good choice
-sigh- Commanders emphasis on color identity in deckbuilding has successfully kept Krrik, Son of Yawgmoth from being a huge problem in the format as a whole, but its still a powerhouse that should be removed or countered on sight against decks with a large or exclusive emphasis on black, as 4 mana can easily become as much as 16, more if life gain enters the equation
At the beginning of your upkeep, you draw a card and you lose 1 life