Chaim Vital

Luria's Boswell and bottleneck: the designated scribe who spent decades wrestling the master's ocean into the Eight Gates, guarded the manuscripts jealously (some were copied from him by bribing his brother while he lay in a coma — the tradition's greatest data-exfiltration story), and left a dream-diary (Sefer ha-Chezyonot) of staggering candor and ambition. No Vital, no Lurianic Kabbalah — only rumors of it.