The deck was originally all high cost Eldrazi and enough mana rocks to get by. Over the first few games it became apparent that I only had high cost cards and few early game plays. Over a few iterations it became apparent that the only Eldrazi I wanted were control pieces and Kozilek. Mana rocks were a two fold gift to Kozilek, there is a considerable overlap with removal spell costs and medium value spells in the 3-5 mana range. With the new direction taking shape I felt that Kozilek became the center and was able to generate value rather than occasionally stop a game finishing sorcery.
A plethora of colorless artifacts to ramp up and supplement Kozilek activated ability. Mana rocks have significant mana cost overlap with the majority of removal spells and 2-4 cost combo and synergy pieces. Colorless begets more utility for the otherwise negative lack of color. Fully colorless rocks either have additional options or provide more mana to compensate.
Colorless producing lands before the Titan was released were always a trade off to restrict their auto inclusion in colored decks. The access to a long history of printed colorless utility lands proves effective for finishing the game and recovering from early mistakes. Standard utility lands for Eldrazi range from Eye of Ugin to Rogue’s passage. Mikikora is usually an end step advantage or counter ability fishing opportunity.
Kozilek is mostly about early prevention of opponents combos as there are limited options to use once they hit the battlefield and no guarantee of mana cost in hand. Counter early and possibly throw Kozilek in danger to cast again and refill the hand. A board wipe is a setback, but not always so with a plethora of mana rocks and a Kozilek cast to fill hand. Forcing a board wipe from a player you know to run several is often to your advantage. Knowing the current political climate is important to force conflicts, not necessarily bargain. Most people don’t like to bargain with a Menace with Menace.