The new Phantom Assassin arcane set is the 1st set I really wanted to buy.

It's a mix of I don't liking Mortred default model (it's too dull with no color contrast) and having really nice effects like the «gravestone» after a kill.

This and Techies arcana are the ones I think are very nice. Arcanas come a long way since Lina one which has just new icons and a tweaked spell effect.