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For the sourcebook see Time of Thin Blood (book)

The Time of Thin Blood is a period in Kindred eschatology that antedates Gehenna by some short period. Traditionally, Kindred scholars have viewed it as a period of political or numerical ascendance by high-generation vampires and optionally Caitiff.

The Time of Thin Blood sourcebook explains that the actual danger of the Time of Thin Blood is not the presence of high-generation vampires, but the deaths of vampires. The death of a Clan member causes a psychic signal to go to the Clan Antediluvian, and if enough of them hit, then the Antediluvian may rise (as was the case with Zapathasura, the Ravnos Antediluvian). Since high-generation vampires are on the low-end of the power scale, they die more easily, and ironically many of the offices instituted to eliminate them (such as the Scourge) make Gehenna come even quicker.