@TRUTH and @TheIdleOne, do you recall when you pulled Sylvasi (and Summer Imp) from the chests, perhaps only before the December 22nd xbox update? And now they haven’t been showing up since?
I have one copy of Sylvasi. I pulled it from an iron key in December. In the XB1 Arena I’ve seen troops like Giant Spider which I’m almost certain is a Steam/PC/iOS troop, and also Grave Knight (long before it was offered for Glory in the Store). I presume that no one is able to pull these additional Arena troops from chests.