Firstly, black is a clunky colour that has poor card filtering capacity and a number of effects that are intrinsically situational or suffer poor scaling
Each guild offers a new game mechanic, which provides players of Limited formats with clear build-around gameplans, such as: Addendum, Spectacle, Riot, Afterlife, and Adapt
They split three sets into two, in what was helpfully called Special Booster ver 2.0 and 2.5
Luckily for those of you in favor of a more "math is for blockers" approach, this will often be way more than enough
Sarkhan Vol 9
Tergrid, God of Fright Tergrid on her own isn't a particularly strong card, but her build-around potential is immense