He went on a killing spree, which unexpectedly created zombies, then escaped.
Bloodwork is a full-on bad guy now, and if this was any other season of The Flash, I’d expect to see Bloodwork continue to develop and elude Team Flash for another 18 episodes or so.
The Flash actually finally took Ramsey Rosso into full villain mode in “There Will Be Blood,” as he realized that he needed to ingest the blood of people he killed due to the fear-induced epinephrine.