I beat the Mantis Lords!
I took a break and went and bought the fragile heart and fragile strength charms. This gave me enough charms to buy another notch. First I had to farm some geo. Then I made my way back and equipped the Longnail, Dreamshield, Thorns of Agony, and Defender’s Crest charms. My intention was to practice a bit and then equip the fragile strength and fragile heart charms. But, I killed the first one pretty quickly and lasted quite a while after that. A couple more tries and I killed them all. Such a relief. While frustrating, it was enjoyable when I saw myself making progress and lasting longer before dying. Then I knew I had a chance.