He is the praetor in charge of the Progress Engine, a Phyrexian faction that believes perfection can be achieved through lethal and unethical experimentation
Unfortunately, Saskia has really fallen out of style and now sits at 86th overall in popularity, which I chalk up partially to the sheer amount of diversity of aggro decks in the format
Cannot be used as Material
It had some minor other notes to play, such as being part of the theoretical Extended Yawgmoth's Bargain deck I was asked to build to show how often it could kill on turn one, and providing the method of execution in some other cases, but Cadaverous Bloom is all about the Prosperous Bloom deck
Your commander costs 4 mana, and your cheapest recurring token generator (Anim Pakal, Thousandth Moon) costs 3, so itll take a minute to set up your board