The idea is to ramp into
Cataclysmic Gearhulk. At the moment I there may be too much land and land search and not enough creatures/removal in the 3-4 cmc area to deal with more aggressive decks.
Permeating Mass is supposed to fill that need but that may not be enough as it will probably die to anything that swings turn 3-4 (brawler,
tracker, etc.). Though they may not want to attack into it as they would lose their creature. Not sure how that will play out yet.