Here is the full list of all 16 Diorama Battle of NINJA 3D achievements.
Defeat an oni
Defeat 1,000 enemies
Ride a gama
Use kage-bunshin
Play a multiplayer game
Defeat a ninja
Defeat a mikoshi
Destroy a houdai
Start a game
Defeat a kobozu
Defeat Benkei
Defeat a byakko
Defeat a tengu
Defeat a juzu-oni
Obtain the title of Deity
Die 100 times