If your opponents opened with an Ignoble Hierarch, Deathrite Shaman or early game Faeburrow Elder or Bloom Tender, prevent them from getting ahead more by tapping down those mana sources
While this can be an issue, since Reanimator decks really want all their creatures in the graveyard, there are ways to work around it
However, not only is Flood of Tears cheaper to cast, it comes with a big advantage: after bouncing everything, you can put a permanent card from your hand onto the battlefield
While things have gotten a little bit better in recent years, its still pretty slow-going
Instead, he had to make due with a slightly less extreme set of threats, most of which were designed to be especially good at beating whatever the opponents best threat was (given the nature of Hypergenesis letting them play their best threat for free)
On top of that, the flavor lore of a Vampire so adept with blood as a media is fantastic