Because Morophon itself is a Changeling, you can cheat it out with Sorin, Imperious Bloodlord, which can then cheat out The First Sliver
I also like the implications of having three of the four cards involved only matter for their type
Qualifier Season 1 (Standard) with Outlaws of Thunder Junction Promo: Steel Hellkite Qualifier Season 2 (Modern, Standard, Draft, or Sealed) with Modern Horizons 3 Promo: Full-Art Mountain Qualifier Season 3 (Standard) with Bloomburrow Promo: Korvold, Fae-Cursed King Qualifier Season 4 (Standard) with Duskmourn: House of Horror Promo: Dragon Tempest Each season offers players opportunities to qualify for the year-end December championship event
Maximum interaction (which means cards that are hard to interact with are more likely to be cut, so no planeswalkers, limited shroud, only temporary spells/abilities give unblockable effect)
Bursty draw and repeatable draw is big in Commander these days, and going over seven cards in hand is easy