If Kruphix leaves the battlefield, that protection ends, and your pool clears out the next time a phase changes
All three colors compete for slots at 3 mana and above, making it less likely you can play them on curve
Either way, theres a lot to like about this card in Standard, Commander, and Wilds of Eldraine Limited where it was an easy P1P1
For example, if Tidehollow Sculler's enters-the-battlefield ability is copied and two cards are exiled, they both return when Tidehollow Sculler leaves the battlefield
But then, all things rot, and from the rot comes life
Each Commander Masters Draft Booster contains 20 cards and 1 double-sided token, including 24 cards of rarity Rare or higher (3: 36%