MTG Salvation

Is it possible to play a consistent 3-color deck in standard without mana fixing? Picking up Red and Green give Mono black such an advantage from the expanded toolbox. We gain cards like dreadbore, rakdos's return, slaughter games, abrupt decay, golgari charm, and Vraska The Unseen. Even Mizzium Mortars could be good for our matchup vs Blood Baron of Vizkopa.

Unfortunately we would have to give up some things as well. Mutavaults can no longer be a full playset and we may even need mana confluence.