Magic: The Gathering: 10 Most Powerful Mono-Blue Cards In 2020 Standard
6. Ominous Seas
Alright so you've countered your opponent's spells, you've drawn a bunch of cards, now how are you actually going to win? Every blue deck needs some kind of win condition. Depending on the degree of control deck you're playing, from temp to full hard control, that can vary. Sometimes it can be a small handful of creatures, others it can be an innocuous little enchantment, like Ominous Seas.
As soon as turn two you can play this Enchantment for one generic mana and one blue. On the turn it comes it nothing happens so you want to be sure you aren't under imminent threat, if you are it can always be cycled for two mana to find a needed removal spell. Once this manages to stick you're off to the races. When Ominous Seas is on the board any card you draw means you'll put a counter on it, at any time you may remove eight of those counters to create an 8/8 Kraken creature token.
When an enchantment that can produce threats just because you're drawing cards hits the battlefield it's hard not to smile. It's also hard not to smile as several 8/8 Krakens swallow up your opponent's life total after you've countered or killed everything they've played.