I recently put some work into designing a disruptive Jeskai deck in Modern, Jeskai Control has been around forever, and today I came across an interesting aggressive Jeskai shell. This is a pretty cool take, utilizing four Spirebluff Canal to push the sorts of spells you can play in a three color deck. ASD put up a 5-0 League result with this creative brew:
You may be wondering why this deck plays Mantis Rider over Delver of Secrets // Insectile Aberration, and/or why it plays Stormchaser Mage over Young Pyromancer- at least, that's where I started. The answer is that this deck is only interested in creatures that both have haste and can survive a Lightning Bolt when pumped with Mutagenic Growth. Once you can convince yourself to play four Mutagenic Growths in a deck that isn't degenerate like Infect and Death's Shadow, this makes a ton of sense. The idea isn't just to be aggressive and capable of interacting with creatures, but also to beat the most played removal spell in the format with a zero mana spell. Throwing a bunch of Phyrexian mana spells in your deck is just a lot easier to accommodate with the new threshold of fastlands available. It's a rather brilliant design in this respect.
The other creature that is absent is Geist of Saint Traft, and while the card is a fan favorite I understand this direction. There is a lot of blocking in Modern right now, and Mantis Rider both flies over the stuff that Geist has to run into while being able to block Inkmoth Nexus. It's true that this deck is quite good at clearing a path, though haste and vigilance combine to make it so that Mantis Rider is much more likely to matter in games where you're behind.
This sort of deck is going to be weaker to spell-based combo decks, though those are definitely at a low point currently. Creatures shouldn't be a huge issue, and as long as your opponent isn't loading up on Path to Exiles and Terminates this looks like it should have significant game against decks that aren't spell-based combo decks.
Unsubstantiate looks a bit suspect to me, though once you register four Vapor Snags it's clear that you care a lot more about Unsummon than Remand. I'm curious to see how the card performs, and will note that it provides some utility against plays like Thought-Knot Seer off of Cavern of Souls.
I really like the sorts of positions this deck can put your opponents in. When you're being attacked by a freshly cast Mantis Rider, do you Lightning Bolt it immediately and risk taking five? Does this deck even give you time to make decisions like that? This is a strong new direction and I'm excited to see if it takes off.