With the wild assumption that Urskaya is indeed going to be released this week, here's next week's event troop.
This spoiler image is fan-assembled from game files, and is UNOFFICIAL
REMINDER: All future troop details are subject to change at any time. (Retrieved 2017-07-10)
Ultra-Rare / Urskaya / Daemon Urska
Spell: Corrupt Crystals (12 Red/Purple) - Explode a gem. Enrage a random ally for every Purple Gem destroyed. Create 6 Skulls. [1:1]
Traits: Nimble / Frenzy / Infernal Armor
Requires: Minor Magic, Arcane Dark Traitstones
Max stats: Attack - 22; Life - 18; Armor - 13; Magic - 0 (When fully ascended and level 20)
Flavor Text: They see me glowin', they hatin'.
Will arrive in 7 days (2017-07-17).