#艦これ版深夜の真剣お絵描き60分一本勝負
From the artist's tweet.

#KanColle Late-Night Genuine 1-Hour Drawing
From the artist's tweet.
"Hissatsu" (lit. Sure Death) is a Jidaigeki television series, well-known for assassins' unique killing styles. Here is the Wikipedia article for one of film adaptations.