Vaal side area

As you explore Wraeclast, you'll occasionally find Vaal-influenced secret areas that are indicated by a glowing, beating heart and swirling ribbons of blood. These corrupted areas have modifiers, similar to end-game maps, which substantially increase their difficulty. At the heart of each corrupted area is a new boss monster, guarding a chest that is guaranteed to drop a Vaal Skill Gem or Vaal Fragment. As corrupted areas require some effort to find and have mods that make them more difficult than normal, you'll often want to invite friends to help you clear the area.