With The Scorpion God or Hapatra in play, you now have access to as many cards as you want to draw, or as many Snake tokens as you want to make
From iconic creatures like Eternal Witness to the meanest of monsters like Atraxa, Grand Unifier, enter triggers are a way of guaranteeing a permanent comes with some value no matter how quickly its removed afterwards
Land destruction is so taboo in Commander that players running the likes of Shifting Woodland or Urzas Saga tend to get away with it Scot free
Rikus deck would be the one to double the number of boogeymen per release
Considering the deck's "go wide" approach, it's not uncommon to get several explore triggers per turn, churn through your deck, and build a hard-to-deal-with board all at once
As the deck is mono-black, this also fits into reanimator themes found in the color