Mono Blue Devotion is still alive and well after Ravnica rotates out and Khans of Tarkir comes in. It will give fits to the new midrange and tempo decks.
With Ravnica gone, it'll be harder to provide devotion for Thassa, God of the Sea and Master of Waves. So their roles are not as important as before. Fortunately, we have a very strong replacement to help us win the damage race. That card is Ensoul Artifact.
Ensoul Artifact is basically the most efficient "creature" in Standard. It's two mana for a 5/5. Sometimes it flies, sometimes it's indestructible. Regardless, many decks cannot handle a turn two 5/5. Even late game, it'll combat with midrange just as good as their own creatures.
One of the best card ever for blue devotion is Cloudform from Fate Reforged. It gives +2 devotion, and grants evasion and protection to our beefy creatures. Flip a 4 or 5 power creature and go to town.
Another new addition is the new blue superstar Clever Impersonator. It can clone any permanent (including creature or planeswalker) on the board. Give the opponent a taste of their own medicine. Because we have synergy cards like Bident of Thassa and Thassa and fliers, we actually have an upper hand to exploit them better than they do. So far it has not disappointed me. It is best against midrange and planeswalker strategies.
So far testing has shown that Mono Blue Devotion (MUD) can go toe-to-toe with the new crop of three-color midrange and tempo. In fact, we have the advantage (about 70% win chance). We have a very simple mana base. We don't take pain from our own lands, and they don't come into play tapped, slowing us down. We have a quick clock with early 5/5 fliers. If unchecked, it can win in 4 turns or less. We have many flying and unblockable creatures to help us race. We have late game bombs like Thassa, Master of Waves, Ensoul Artifact and Clever Impersonator. We have tempo cards like Singing Bell Strike to slow them down, while our creatures go in unblocked through the air or with Thassa's assistance.
Mono Blue Devotion will have to go a new direction without good devotion enablers. Devotion is still a strong mechanic, so Thassa and Master of Waves is not going anywhere. Fortunately, we can compensate with cheap, fast clocks, late game bombs, and tempo utility spells. Try it out for yourself against other top decks of the new Standard. You won't be disappointed.
