Green Slime
The group walked through the arched door slowly and cautiously. For whatever reason Jack still hadn't come back and wasn't replying to Ray's message.
Walking past and through the door, the room was covered in darkness making it hard for them to see anything.
Also, the red aura that Ray had seen up to this point suddenly vanished as soon as they had entered the room. Indicating that either his Dragon eyes skill was being suppressed or whatever he was looking for was able to hide its presence.
Gary was the first person to discover something.
"Over here!" Gary shouted as he lifted his light crystal to reveal a human figure stuck to the wall.
"It's Jack!" Badger said.