It may be an artifact, but it's one of the biggest reasons to play black mana in Standard right now
River Song River Song puts maximum value on any scry effects you have
Im definitely going to be putting Jaxis in my Feldon of the Third Path deck, since pitching a large creature to the graveyard to copy with Feldon is exactly what I want to be doing and making a large creature with Feldon is often going to be what I want Jaxis copying
In fact, I believe Emeritus of Truce is the second best card of this cycle
If you want one for your collection as an historical trinket, I recommend reaching out to Keith Adams on facebook or similar and he can probably hook you up
Best White Token Commanders (God-Eternal Oketra, Prava of the Steel Legion, and Darien, King of Kjeldor) Mono-white token decks can be built a lot of different ways, as represented by the wide array of effects of these legendary creatures