From publisher blurb:
In this issue of the Character Expansion Handbook, Alexander Augunas unleashes biohacker secrets and serums galore with all-new biohacker class features, fields of research, and theorems. Specialize in new fields such as metamorphology to alter the physiology of friend and foe alike, biomedicine for healing the sick, pathology for manipulating contagions, and more. You'll also be able to specialize in a brand-new type of hybrid medicinal called nostrums, which allow Starfinder characters to create spell gems in drinkable (or injectable form). And what good would such an item be if there wasn't a nostrum specialist biohacker to recreate your favorite alchemical characters? You'll also be able to pick from a massive list of theorems, including new synthesis theorems that allow biohackers to spontaneously generate a limited number of items whenever they rest, whether that be medicinals for saving lives, poisons for ending them, or biotech augmentations for making life a little stranger!