MScore: 9.7/10
Ugin, the Ineffable
Legendary Planeswalker — Uginrare
Colorless spells you cast cost 
less to cast.
+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.
−3: Destroy target permanent that's one or more colors.
4
Illustrated by Daarken · War of the Spark · #2
Rulings for Ugin, the Ineffable
7
2019-05-03
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Ugin). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.
2019-05-03
A colorless spell whose mana cost is {2} or {1} will cost {0} to cast.
2019-05-03
Once you look at the exiled face-down card once, you may look at it again any time you wish. If another player gains control of the Spirit token, that player can't look at the exiled card.
2019-05-03
If the Spirit leaves the battlefield for any reason, you'll put the exiled card into your hand, even if Ugin left the battlefield before that happened.
2019-05-03
If you've activated Ugin's ability multiple times, you must keep track of which exiled card belongs to each Spirit token.
2019-05-03
If an effect such as that of Doubling Season causes Ugin to create two Spirit tokens, you still only exile one card from your library. You'll put that card into your hand the first time that either of the tokens leaves the battlefield.
2019-05-03
A land normally has no color, even if it can produce one or more colors of mana.
(You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)