This ability gets around Commander tax, reducing its cost down to just one black and one red so long as you have enough artifacts out
If you combine them together, which isn't much of a stretch considering they share many of the same cards (the big difference is the GR version plays Dragonlord Atarka), Gx Eldrazi Ramp would slot in as the fourth most played, ahead of GW Megamorph and behind the three pillars that make up about 40 percent of Standard: Abzan Aggro, Atarka Red and Jeskai Black
That means Mazes End, Gaeas Cradle, Cabal Coffers, Dark Depths, Glacial Chasm, or whatever other land you want to build around now has a commander tutor
Sorcery Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle
Rakdos, Lord of Riots Rakdos, Lord of Riots is an excellent Rakdos commander if you like to cast big colorless creatures, like the Eldrazi battlecruisers