At first blush, Shadrix appears quite similar to Rankle, Master of Pranks a proven success in Standard aggro and midrange lists
Its desire for creatures with high power fits nicely with green, and the strong enters ability pairs well with blues many flicker effects
They could fit well as part of the 99 of, say, a Tribal Angel deck
Drag to the Roots Golgari decks excel at milling themselves, so it only takes a little more work to enable delirium to make Drag to the Roots an exceptionally cheap removal spell for its lack of conditions, plus 4 mana to destroy anything isn't a terrible rate in its own right
Speaking of diving Clue #1: The Three Take a look at Mist-Cloaked Herald, whose art is by Anthony Palumbo
A fair number of cards can be cut, and a few cards seem incredible that they left out