"Part 1: The Summoning"' is the fiftieth issue of the comic book series The Unwritten, and the first issue of the five-issue crossover event The Unwritten Fables, released on June 26, 2013.
Publisher's summary
An extra-sized issue celebrating fifty issues of THE UNWRITTEN and the start of “THE UNWRITTEN FABLES,” a 5-issue storyline that drags Tom Taylor into the heart of a world he never made from the pages of Vertigo's hit series FABLES. The mundane realm of humanity and the fairy-tale homelands have fallen to a terrible foe. In desperation, the witches of Fabletown gather to summon the greatest mage the worlds have ever seen. And are they in for an unpleasant surprise...