The following story synopsis appears in the Oath of the Gatewatch Player's Guide. The Oath of the Gatewatch story continues to unfold each week in Official Magic Fiction.
There are many important moments in the Oath of the Gatewatch story, but the five most crucial are shown on cards. You can read more about these events on the Story tab of OathOfTheGatewatch.com.
The Rise of Kozilek
Moments ago, Ob Nixilis destabilized the hedron network the Planeswalkers had assembled to trap Ulamog. The Planeswalkers continued to fight, hoping they could still defeat the titan. But the quaking ground gave way and the titan Kozilek rose, accompanied by thousands of Eldrazi of his brood lineage. Kozilek crashed through Sea Gate, toppling the lighthouse and destroying the dam. The Zendikari army and the Planeswalkers scattered, with Kiora planeswalking away from her home world in despair. It seemed that Zendikar was doomed.
Retaliation by Ob Nixilis
His Planeswalker spark reignited, Ob Nixilis could have left Zendikar, but he was obsessed with exacting revenge on Nissa for reclaiming the Khalni Heart from him. In the chaos following Kozilek's rise, Ob Nixilis cornered Nissa. When Jace and Gideon came to her aid, Ob Nixilis used a horde of Kozilek's brood he had bent to his will to overpower all three Planeswalkers. He planned to lock them away for good, but Chandra showed up in time to foil his plan. Together the four Planeswalkers drove Ob Nixilis from the plane.
The Birth of the Gatewatch
Gideon, Jace, Nissa, and Chandra emerged from Ob Nixilis's prison. With two titans rampaging across the land, it looked like Zendikar's end was nigh. Gideon turned to the others, urging them to stay and fight. He believed that together they could save Zendikar—and more, he believed that they could use their gifts, their Planeswalker sparks, to protect against all forces that threatened the Multiverse. The others were moved by Gideon's sincerity. In turn, each of them took an oath to work together to protect the people and planes of the Multiverse. Thus, the Gatewatch was born.
Zendikar's Final Stand
The Planeswalkers of the Gatewatch battled their way across the corrupted landscape in pursuit of Ulamog and Kozilek, destroying hundreds of lesser Eldrazi along the way. Though they could no longer use the hedrons, they had a plan. Jace had identified a leyline pattern that would hem in the two titans, so with Gideon and the Zendikari survivors corralling them, Nissa—whose powers extended far beyond what she and others had realized—bent Zendikar's leylines into the pattern. That was Chandra's cue to unleash a continuous blast of fire. Augmented by the mana of the bonds Nissa had created, the fire destroyed the two titans.
Exhausted, the four Planeswalkers stood on a floating rock high above the land they had saved. They had accomplished something together that they could not have achieved working separately. Below them, a glyph mirroring the pattern Nissa had created stood out against the corrupted ground, glowing bright green. As they watched, the lines of the glyph erupted with verdant growth. Life would return to the plane, and Zendikar would one day flourish again. Though the battle was won, the Planeswalkers knew the war was far from over. There was a third titan, and whether on Zendikar or another of the myriad planes of the Multiverse, the Gatewatch would find Emrakul and vanquish her before she could destroy more worlds.