Dies to Removal

When I've tried Eldrazi, Swiftfoot Boots in addition to Greave proved a pretty good idea. I'd also recommend considering Pathrazer of Ulamog, maybe even Ulamog's Crusher.

No Mana Vault?

Mindslaver didn't make the cut? Strip Mine, Tectonic Edge?

Removal options aren't great: Avarice Totem, with the stacking trick? Brittle Effigy? Spine of Ish Shah? Probably don't want to board wipe, aside from All is Dust - but on the other hand, Eldrazi do well against an empty board.

Card draw options are hard to come by. Mangara's Tome? Phyrexian Portal? Mind's Eye is probably too slow.

Urborg, Tomb of Yawgmoth? Doesn't have a color symbol, but it turns on some of your lands, like Arena.