That is the joy that is magic, there is always a solution to a problem, you just have to recognize when there is a problem and respond accordingly
Descent into Avernus puts the game on a short clock, and I am here for it
When the card is first played, you can draw a card then choose one from your hand to discard
There are a few cards that do both but they are only a handful of cards that are really only a one time use- hardly of use for this kind of a deck that likes to reanimate all creatures in the graveyard
Electric Seaweed Electric Seaweed puts a red spin on Massacre Girl by dealing damage rather than reducing toughness, which opens the door to many synergies
Relevant interaction for Reanimator tends to look more like Counterspell and Thoughtseize than Doom Blade, but you do want to keep an eye out for some removal in case you run afoul of a Scavenging Ooze or Containment Priest