The trick, of course, is making sure your high-mana finishers are on top of your library when you draw them
Black lacks good lands as outlets
Generally, this issue raises up by having either a plus or a minus thats way better for their cost than other options, so the choice will always be to activate that one ability as much as possible or get to it as much as possible
Disturbing Mirth This is a curve I am interested in: The Jolly Balloon Man This is a combo I am interested in, particularly because it involves one of the most powerful cards in the format
They also have, Whenever you cast a spell with X in its mana cost, create a 0/0 green Hydra creature token, then put X +1/+1 counters on it. That means that youll be generating an extra Hydra for nearly every Hydra you cast
It has many ways to do this across the formats, including looping Jeskas Will or gaining it through the likes of Chandra, Torch of Defiance