Swim

From MUME

Swimming is a ranger skill that allows you to enter rivers and lakes without a boat and survive. It is also the only way to enter underwater places.

Your swimming skill will be checked each time you enter the water, when you try to get back on the ground, when you move from a water room to another and every few seconds spent in the water. Failure means that you gulped some water and choked.

Swimming will also consume your movement points quickly. You will drown if you become exhausted while swimming, or if you fail too many checks. Finally, when swimming underwater you must also take into consideration how long you can hold your breath. Underwater fights are particularly bad for your health, unless you can resurface quickly.

The "swim" command switches on and off your ability to swim. When "swim" is turned off, you will not enter the water by moving, fleeing or following someone, unless you have a boat. It is possible, however, to teleport or to fall from a cliff into a river.

Example:

    > swim
    Ok, from now you'll try to swim.
    W > swim
    You won't try to swim anymore.
    >