Were there any close runner-ups you considered
Youve got to toss two cards unless one of them is a creature, which makes this perfect in creature-heavy builds
If you're tutoring for anything and don't have this accessible yet, you're tutoring for Parharmonicon
For most of these, I wanted to attach the ability to relatively expensive cards that have narrow uses, but really come in handy sometimes in Commander games
Narfi provides consistent tribal buffs and recursion as long as you commit to snow mana
Also, for an additional cost of one of each mana type, you may untap all attacking creatures, giving them trample, lifelink, and haste until the end of the turn, and trigger another combat phase