She's the perfect example of a card that is an enabler and a payoff in one: she's a better Corrosive Mentor as a 4/4 with menace and she turns into a card advantage engine when creatures die from wither, sweepers like Darkness Descends, blight from Lorwyn Eclipsed , Toxrill, the Corrosive, and all the payoffs like Nest of Scarabs that she's backwards-compatible with
A high-cost Character with 5|6 stats that can be used in slow decks, especially ramp ones, but he cant be inked, so thats a downside
It seems limiting at first glance, but my mind again goes to Commander and all the creature typal themes players build in that format
That means Jace just never survives, but thats not the case here
Luckily this is better than most of those, it just means it is less of a step up from a swamp than it would have been some years ago
Do black cards have a good card draw