This paper explores Oshii Mamoru's films and animations. First, his view of the cinematic citation (appropriation) is analyzed in some comparison with Jean-Luc Godard. Second, his preoccupation with the plot of the weird duality between reality and dream is examined with plural contexts of cultural avant-garde in the 20th century. Third, the question of why Oshii Mmoru has been so much interested in the warfare in his works. Through the series of problematics, this essay would locate his perspective in some philosophical and ontological debates, in which Deleuze & Guattari and others must be addressed. Then, his insightful but provocative statements on the war and history are interpreted in the philosophical streamwhich I would like to call Machine-Oriented Ontology.