So this is an Eldrazi themed Tribal Deck.

At first I wanted to put all the Eldrazi Tribal noncreature Spells in, they are quite powerful (see All Is Dust). Then I came to the conclusion I should decide whether or not to make use of the masses of Eldrazi Scions, Spawns, Horrors and whatnot token generators. I liked it better without that stuff, so putting in Skittering Invasion seemed senseless. Along with the real Tribal spells I found some colorless spells that fit the theme quite nicely but without the right recursion seemed a bit out of place.

In the course of putting the list together at some point I figured it might make more sense to get rid of Instants and Sorceries completely and rely on creatures and artifacts. Some of the artifacts seems out of place here as well (Heirloom Blade is one of those) but they offer some nice Tribal Synergy, so I kept them in although they don't fit the Eldrazi Theme too much.

Having Morophon as the Commander combos nicely with Fist of Suns, they also make the color-dependent Eldrazi castable from only colorless mana.

Conduit of Ruin and Deceiver of Form are another nice combo, make your creatures all get Annihilator 4 or make them become It That Betrays with Annihilator 2 and you get everything sacrificed.

Gotta playtest it a bit if it is even considerable fun, will indeed work on the deck further as soon as I can.