Collecting chapters 47–50 ("Children," "Someone," "Charge," "Scream"), Volume 12 of Attack on Titan follows Erwin and the Survey Corps as they mount a rescue operation to retrieve Eren from the Colossus and Armored Titans, without the numbers to fight safely outside the walls. The volume was serialized in Kodansha's Bessatsu Shōnen Magazine in Japan (December 2013) and released in English by Kodansha Comics (April 2014), translated by Ko Ransom.
Genre, pace, audience and core tone below are recorded at the series level, not verified volume-by-volume: Wikipedia's infobox lists Attack on Titan's genres as action, dark fantasy and post-apocalyptic, and its official demographic as shōnen (Bessatsu Shōnen Magazine). The series is known throughout for a grim, high-stakes tone and fast-moving combat, which this volume's rescue-and-betrayal chapters continue.