風林火山 (hiragana ふうりんかざん, romaji fūrinkazan, historical hiragana ふうりんくわざん)
A contraction of the slogan on daimyō Takeda Shingen's army banner, 「疾如風、徐如林、侵掠如火、不動如山」, originally from Sun Tzu's The Art of War