16 Omarthis, Ghostfire Initiate Manifest Your Deck Away Colorless decks need to dump a lot of mana into something, what with all the powerful mana rocks and lands that can produce extra mana, so why not have a commander that can make use of all that mana
This means this deck is debuting a few aesthetically unique cards beyond the Rainbow Foil centerpiece cards
You can build around it, and Ive even seen an Umori, the Collector companion build with Sapling of Colfenor, but for what it does, Id rather have something else in the command zone
Based on this card alone, this could be a deck that focuses heavily on interaction with the graveyard to discard and recall lands, but more realistically, it is likely that the deck will be set up to pull mana from sources other than just lands to allow for the discarding of lands without it impacting the deck too negatively
What I mean by this is that you can build a deck that is more likely to be able to utilize an expensive bomb by tinkering with its supporting cast
Spirit of Winter will never reach the heights of the D23 Elsa - and the price may go down if the meta stops favoring the card - but it's worth a decent amount as far as trading cards go
