It only takes a couple of combats for Otharri to build a dominate board state
Having a significant portion of a set's value concentrated in what essentially amount to foil mythics in terms of rarity makes opening boxes and packs an extreme gamble for the average player, and this had lead to some complaints
Once your opponent's defense is down, seal their fate with a few larger creatures
Its colorless, has a reasonable mana value, and its easy to crew
For instance, Arid Mesa can be sacrificed to search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle. While this can be used for basic lands of the stated types, it can also be used to fetch nonbasic lands with the given types
First, this card is by and large going to be better the more colors a deck has