年忘れぐだぐだオーダー2016

Oda Nobunaga will join the fight for "GUDAGUDA Honnouji" that suddenly appears at Chaldea! This event features an original story written by none other than the one with a super confusing pen name, Keikenti-san! Of course, the scenario was (basically not) supervised by Kinoko Nasu!

(Source: Fate/Grand Order Wiki)