Without development, the ability to swim is limited to being able to thrash around and keep one’s head above the water for a short time. Higher Swim percentages indicate being able to negotiate deeper and stronger waters, with less risk of drowning. Making a Swim roll therefore depends entirely on the conditions. Rough seas, strong currents, white water and rip-tides all reduce the grade of the skill no matter what the character’s affinity for water might be. Under normal conditions a character’s maximum swimming speed per round is equal to their base Movement rate, plus an extra meter for every full 20% they possess in Swim.