Ooh, boy. This is quite the deck.Ten counterspells highlight this Mono-Blue Control deck, which buy time for big finishers Icefall Regent and Ugin, the Spirit Dragon. Keeping the board under control is clearly difficult in Mono-Blue, so Perilous Vault is necessary, but we need something else. We could play more Voyage's Ends, but perhaps there's something better.
Is playing Encase in Ice maindeck crazy? If your opponent is playing creatures, chances are they're playing green or red. If they aren't playing creatures, your removal spell would likely be pretty bad against them anyway! Overall, it doesn't seem that crazy if you don't have any other good options.
The cool thing about being Mono-Blue is that you have a lot of leeway in how you build your manabase. For example, you don't need to stress too much about always having your colors since you have nineteen sources of blue mana. That means you have a lot of room for cool colorless lands, such as Radiant Fountain and Haven of the Spirit Dragon. Going long, you have additional threats and lifegain thanks to your manabase, both of which are things that help a control deck.