The sight of the weathered and upset man tying himself to the rock struck the party as somewhat odd; some are frightened, others curious, but all seem to have concern for the man.
Knives and Lorrias move quickly between the rotting bodies and get close to the man, yelling variations on “Why?” and “Stop!” while the Dragons also call from a distance. As they get closer, Lorrias readies a spell to incapacitate him, but before he can get close enough the man jumps up, arms by his sides and legs together, and nudges forward. He lands into the lake with a splash, the rope being pulled from its coil by the side of the rock. It seems there is quite a length of rope there, enough for a dangerous depth. The end of the rope is tied to the rock.
From what can be seen, the other end being tied to the rock suggests the man wants to find his way back up at some point. Perhaps this isn’t a suicide attempt. The water smells awful, and incredibly salty. It bubbles slightly, and a green-white froth sits at the edges. The water looks very blue, but also full of dust and sand to the point that it’s hard to see more than a few iches in depth. From what can be seen, the man is gone.
What do you do?
Lorrias and Knives need to make Constitution saving throws (1d20 + your Constitution modifier + your proficiency bonus, if applicable)