The Final Getsuga Tenshou in the anime "Bleach" is the final technique that the main protagonist, Ichigo Kurosaki, can use with his Zanpakut? Zangetsu. Using this technique transforms Ichigo's physical appearance and allows him to use the technique Mugetsu, but it does cause negative effects for him.
As of 2014, Ichigo has only used the Final Getsuga Tenshou during the final confrontation with S?suke Aizen in his final evolutionary stage. The use of Mugetsu allowed Ichigo to damage Aizen's form severely, causing him to revert to a previous evolutionary stage. After the battle, Ichigo lost the majority of his Shinigami powers and was unable to use them until they began regenerating after a skip in the manga's continuity.