Twisted Embrace:
Twisted Embrace is a nice take on the removal based auras like Cartouche of Strength. It's a strictly more powerful version of those auras as it just straight up kills creatures, however black already has a strong identity when it comes to creature removal. Worth a test as it operates differently and allows you to outgrow your opponents creatures netting you more advantage in board stalls, but I can see this not being as objectively powerful as it first seems.

Tamiyo's Safekeeping:
Tamiyo's Safekeeping is similar to Vines of Vastwood but plays more like a defensive trick then something you would play in aggressive strategies.

Careful Cultivation:
There are plenty of ramp options in the two and three drop slot, but I'd like to note that it was worth noting this particular card as it can do more than just give you a two drop ramper in a pinch but also acts as a means to grow a hard to remove body.

Moonfolk Puzzlemaker:
Doesn't have to attack, has a better body than Library Larcenist. May not draw you a card but there are multiple ways to have this card turn sideways.

Moonsnare Specialist:
There are a lot of bounce effects on creatures with Aether Adept and Man-o'-War being in the cube, this doesn't really stand out. It is another means of picking up those creatures however and is definitely worth investigating whether it should be a mainstay.

Tamiyo's Compleation:
While it's not completely the same as the other frost effects, this card manages to also give blue an answer to troublesome permanents. That's right not just creatures but also artifacts, enchantments, and/or utility lands that we may see in the future.