In Botanica, near the end after the demon boss, there are enemies named Sunseeker Gene-splicers. They have an AoE called Death & Decay that is unique. Instead of doing a set damage, it's a percent of enemies health. This provides much utility when thought about logically. You can use it on mobs, or you can chain-MC and use this ability on bosses. That's right. You can take a mob that does a set percent of damage and set it against a boss, making the fight easy. I did this a while ago, and I can't remember whether it was Heroic or not. Don't know if it would even make a difference, but disclaimers ftw. Glad I could finally contribute.