I have an affinity for tempo decks. And for the last five years, Delver of Secrets has been synonymous with tempo. Unfortunately, Delver of Secrets has underperformed in Modern. The amount of cheap removal, especially Lightning Bolt and Abrupt Decay, has stymied the little Insect that could, relegating it to the fringe of the format and a near-afterthought even in decks like Grixis Delver that don't seek to play the "protect the queen" strategy unless absolutely necessary.
The real issue is that it's too hard to gain tempo against the great removal in Modern while also being prepared for fast combo. You don't have access to the cheap countermagic, Daze and Force of Will, that is a hallmark of Legacy Delver decks.
Or do you?
Travis Woo first brought Disrupting Shoal to the attention of Modern players with his clumsily named NinjaBearDelver archetype. Disrupting Shoal lets you raise the curve of your deck a bit without worrying about having cumbersome draws, since you can pitch cards that would otherwise sit in your hand. This not only gives the deck access to some free countermagic but also allows it to increase in overall power level, which has been a problem for Delver decks in Modern before.

Unfortunately for Travis Woo devotees, Ninja of the Deep Hours and Phantasmal Bears aren't exactly suitable Modern cards, but this updated list by Arthur Fusco has cut the chaff through the addition of Thing in the Ice, a card that absolutely will win the game if left unchecked for more than a turn or two. Between Thing in the Ice and Vapor Snag, you should be able to keep your opponent's battlefield clear long enough to get them dead, or at least bring them into Psionic Blast range.
The Cryptic Commands would normally be untenable for an eighteen-land deck, even one sporting twelve cantrips, but being able to pitch them to Disrupting Shoal mitigates their diminishing returns, which is great, because as far as functionality is concerned, Cryptic Command is the ideal card for a deck like this. You can clear the way for a lethal attack, answer anything in play or on the stack, or dig for a lethal Psionic Blast.
Even though tempo decks are aggressive, they rely on their versatility because you have to interact with your opponent once your clock is in play. Since you give your opponent time to develop while you establish a clock, you have to be prepared to answer something on the battlefield or still in hand, and Cryptic Command allows you to do so.
Losing Lightning Bolt is a big deal for a deck like this, but the gain of Disrupting Shoal is excellent. It makes the mana easier and less painful, and it makes the deck nearly impossible to play against, since your opponent will always be off-balance. For more information about the deck from its designer, check out the deck tech here. And may your Delvers always transform on turn 2.
Mono-Blue Delver
Arthur Fusco
73rd Place at Grand Prix on 8/27/2016
Modern


Creatures (14)

4 Delver of Secrets
4 Snapcaster Mage
4 Thing in the Ice
2 Vendilion Clique
Lands (18)

9 Island
1 Flooded Strand
1 Misty Rainforest
2 Mutavault
1 Polluted Delta
1 Prairie Stream
3 Scalding Tarn
Spells (28)

3 Cryptic Command
1 Deprive
4 Disrupting Shoal
3 Psionic Blast
1 Redirect
4 Remand
4 Vapor Snag
4 Gitaxian Probe
4 Serum Visions
Sideboard

3 Vedalken Shackles
3 Commandeer
2 Hibernation
3 Hurkyl's Recall
1 Redirect
2 Geist of Saint Traft
1 Jace Beleren