Obviously missed that they added this beauty
. It's an excellent rush item for roaming mages, offering great sustain and a decent amount of AP and mr.
That said, are there any item niches you feel need to be filled? Just making an item for the sake of a new item is bad design. Making an item to fill a hole in gameplay opportunities is the main objective.
Personally, I think an iteration of the Rite of Ruin, Pox Arcana, Trickster's glass, and Martyr's Gambit from black market Brawlers should be added to the game permanently. Rite of Ruin offers excellent tower pushing strength (something many mages lack), Pox Arcana offers in fight mana sustain and burst to AoE utility mages, Trickster's glass is just cool period. Martyr's Gambit may need more tuning (like higher health, maybe % damage reduction on the active, and obviously a higher total cost to match), but it is the kind of item tanks dream about.