Having multiple opponents makes this card a bit more effective
When I first saw Grim Monolith at the Urza's Legacy prerelease, my eyes almost fell out of their sockets
Despite its high initial casting cost, there are plenty of ways Prismari decks can hit this casting cost and still have mana to spare, so that's why it takes pride of place at the top of our ranking.
Well, it says that if you spend your mana on an X spell, you get to draw a card and gain life equal to half of X, rounded down
Alternatively, there are cards out there which can let you strategically turn counters into other resources or creatures with unique spell effects that trigger when you place counters on them
Almost every LGS will have some on their shelves, and theyre often well priced