15.17 Swim

The Swim skill is one of the most narratively narrow skills, but it can still be very important in aquatic environments. There are no specific rules for catastrophic failure, because the consequences depend on the context. For example, muddy water with many weeds might very hard to swim through quickly, but you wouldn’t be much more likely to drown in it by swimming across the surface than you would in calm water. A creature in full plate might also sink like a stone without active effort, while an unarmored creature can usually stay above water by simply floating still. Feel free to decide that a creature who fails a Swim check by a large enough amount sinks underwater if it seems appropriate.