Swim
Swimming is an inherent ability of all player characters, and some mobs, which allows one to travel in and under water. Swimming is slower than running, but faster than walking.
When your character is in the water, press the sit key will dive deeper, while pressing the jump key will surface. You can hold the left mouse button to look around. You can hold the right mouse button and then move your mouse up and down to change your swim direction. Moving your character forward or backwards will then make them swim in the direction you have chosen. As a ghost or while water-walking, pressing both mouse buttons and angling the camera downward will allow your ghost to swim.
When underwater, a character begins to run out of breath and may drown. Resurfacing will allow the breath bar to slowly refill. Some underwater places have 'pockets of surfacing air' visualized as underwater air bubbles coming from cracks in the crust or barnacle-like models - you can stay there and fill your breath bar. These pockets are usually places in places related to some underwater quest. Deeper waters (such as around the continents) will fatigue characters, whether they are above or below the surface. When either the breath bar or fatigue bar expires, characters begin to take damage. Both drown and fatigue damage can be healed, allowing the character to go on for a little longer.
Ghosts do not have to breath underwater, but are still affected by fatigue and can be killed a second time.
Aquatic speeds
| Movement type | yd/sec | Run % | Swim % |
|---|---|---|---|
| Normal swimming | 4.7222 | 67.46% | 100% |
Normal swimming with Swift Landing [Azure Silk Belt] [Glompmaw's Ring] |
5.4306 | 77.58% | 115% |
 [Unending Breath] |
5.6667 | 80.95% | 120% |
 [Hook of the Master Angler] |
6.375 | 91.07% | 135% |
 [Speedbarge Diving Helm] (swimming) |
7.5556 | 107.94% | 160% |
Most aquatic mounts [Travel Form] [Swim Speed Potion] [Shimmerscale Diving Suit] [Pocket-Sized Computation Device] via  [Slipstream Generator] |
9.4444 | 134.92% | 200% |
 [Sea Legs] (swimming) |
10.3417 | 147.74% | 219% |
 [Feast of the Fishes] |
10.6250 | 151.79% | 225% |
| [Speedbarge Diving Helm] (running) [Sea Legs] (running) |
11.2 | 160% | 237% |
 [Underlight Angler] with  [Underlight Blessing] |
11.8055 | 168.7% | 250% |
 [Cursed Swabby Helmet] |
14.1666 | 202.38% | 300% |
| [Sea Legs] on most aquatic mounts |
18.8889 | 269.84% | 400% |
 [Vashj'ir Seahorse] |
25.9722 | 371.03% | 550% |
Mounts
- Main article: Aquatic mounts
There are swimming mounts that are specifically desgined to increase swim speed, with the caveat of only being truly useful in water. Many are gained through fishing or fishing up a currency, looting a rare, as a rare drop, or as a quest reward. Examples include:
Underwater Walking
- Main article: Underwater Walking
Underwater walking is a new movement mechanism introduced in Cataclysm that allows the character to function as if he/she is on land when standing or walking on the seafloor. This includes water breathing, the ability to eat or drink while on the seafloor, the ability to mount on the seafloor, and increased movement speed while not mounted and walking on the seafloor.
Methods to breathe longer underwater
- Main article: Breath
- Several items, including
[Hydrocane], 
[Mastercraft Kalu'ak Fishing Pole], [Deepdive Helmet] and 
[Band of Icy Depths] allow underwater breathing while equipped. - Alchemists can brew
[Elixir of Water Breathing] and 
[Elixir of Greater Water Breathing]. - Warlocks have a castable [Unending Breath] buff.
- Often, underwater quests will provide a summoned item that will provide underwater breathing.
- Certain quest rewards, such as
[Nagrand Cherry], allow short underwater breathing buffs. - Druids in their Aquatic Form can breathe underwater. Switching to Aquatic Form after an underwater fight is a convenient way to take a breath before the next fight.
- Undead players have no need to breath, due to their
[Touch of the Grave] racial trait.
Methods to bypass the need for swimming
- Water-walking spells such as shaman's
[Water Walking], priests' 
[Levitate], and death knights' 
[Path of Frost]. - While dead, all characters can intrinsically water-walk.
[Inflatable Mount Shoes] allow a character's mounts to water-walk.- Characters with the appropriate riding skill can fly over water with flying mounts.
- Various items and toys:
[Elixir of Water Walking], Gunshoes, 
[XA-1000 Surface Skimmer], 
[Anglers Fishing Raft], 
[Tuskarr Dinghy].
Additional notes
- Swim speed, unaffected by anything, is just a bit over two-thirds the speed of running.
- Regular mounts are able to swim, although they travel no faster than an unmounted player. Originally, entering water while on a flying mount would dismount the player.
- You can escape combat from some mobs if they can't swim; for example, a wolf.
- You can escape combat from some swimming mobs because they can't leave the water; for example, a threshadon.
- In the event of an encounter where you do use the transition between land and sea to break a fight, the mob in question will evade but remain in combat with you. It should, in most cases, reset within a few seconds.
- Some amphibious mobs can pursue from land into the water and swim after you or from water to land and run after you. For example, a murloc. Unless you have a method of reliably swimming fast while in combat, it would be a very bad idea to try escaping such mobs by swimming.
[Draenic Swiftness Potion] and [Shimmerscale Diving Suit] are other options that can be consumed to increase swim speed.