This mechanic was introduced in 2018. Some monsters can inflict the bleed status effect when they hit you. This status effect always lasts for three turns in combat; it cannot be cured with any item and waiting will not cure it, either. The only way to get rid of this status effect is to attack three more times and suffer through the bleed damage.
During each turn of combat in which you participate while afflicted with the bleed status effect, you will take 1-6 bleed damage before your move, potentially dropping you to zero HP before you can attack at all. If a monster inflicts this status effect on you while you are already bleeding, the amount of bleed damage taken per turn will remain the same, but the counter will reset back to three turns.
During each turn of combat in which you participate while afflicted with the bleed status effect, you will take 1-6 bleed damage before your move, potentially dropping you to zero HP before you can attack at all. If a monster inflicts this status effect on you while you are already bleeding, the amount of bleed damage taken per turn will remain the same, but the counter will reset back to three turns.
Lore Wiki » Epic Weeks » Common Epic Week Features » Status Effects » Bleed