Battle for Zendikar returns the storyline to Zendikar, a plane of adventure, many treasures, and potent mana supplies. The plane is littered with large, floating polyhedron-shaped stones called Hedrons, that were created by Nahiri, the Kor Lithomancer. Together with Ugin and Sorin Markov she used them to trap the horrendous Eldrazi on the plane. Thousands of years later, the meeting of Sarkhan Vol, Chandra Nalaar and Jace Beleren in the Eye of Ugin chamber unintentionally loosened the bonds that kept the Eldrazi in torpor. The Eldrazi were finally released by the elf Nissa Revane, thinking that they would leave Zendikar far behind them. She was wrong. Two years after the initial destruction, at least Ulamog is still around.[9] Now, Gideon Jura takes the lead of a group of planeswalkers in facing the Eldrazi alongside the residents of Zendikar. Meanwhile, the trapped planeswalker-turned-demon Ob Nixilis is desperate for a way off of the plane. The five cards that represent the pivotal moments in the storyline are Gruesome Slaughter, Nissa's Renewal, Ugin's Insight, Outnumber and Aligned Hedron Network.