For those who aren't familiar with Slay the Spire (or only passingly familiar), the context here is that I started with a hand of 5 cards that was pretty lackluster and then played a Swift Potion to draw 3 more cards, and then the resulting hand I got was extremely bad. I ended up getting destroyed this fight.
Had I gotten a different boss relic (other than Black Star) I likely would have survived this fight. Black Star is kind of a greedy play and I gave into the greedy play and deeply regretted it.