User blog comment:Crimson and Darkness/Volume 25 discussion blog/@comment-2402:3A80:D75:D7A8:AB83:6EFA:2D12:594-20180309171525/@comment-86.149.138.216-20180310011255

The full form is because the form Issei is using at the moment has been nerfed by ophis because the full power of it almost killed him.