Shapeshift into aquatic form, increasing swim speed by 100% and allowing the Druid to breathe underwater. Also protects the caster from Polymorph effects.
The act of shapeshifting frees the caster of movement impairing effects.
Immune to Polymorph effects. Increases swim speed by 50% and allows underwater breathing.
Aquatic Form
Also known as a sea lion, druids obtain Aquatic Form form from any trainer at level 16. One can only use the Aquatic Form while swimming, but can travel normal running speed in water and will not run out of breath (water breathing). Take note that this 50% increase is of the 66.6% base swim speed, hence giving a 33.3% bonus. Thus, the net effect of this form is to allow you to move at 100% normal running speed in water.
The downside of this form is that it has no defensive capabilities whatsoever, meaning that in a combat situation it's only really useful for escape. Outside of combat however, it has a large number of potential uses. The speed bonus means that it can serve as a fast form of travel if a given destination can be reached via water, and the greater presence of rivers in Alliance territory means it also gives Horde druids venturing into that area with numerous opportunities for concealment, reconnaissance, and rapid escape as mentioned above. The form can also be exceptionally useful for druids with the Herbalism tradeskill, as it allows more rapid harvesting of the herb Stranglekelp, which is valuable on many servers.
While in Aquatic Form, you cannot cast spells or talk to NPCs. You are also considered a Beast so spells that target Beasts can be used on you ([Hibernate] for instance).
Your caster form will start regaining mana 5 seconds after you change to Aquatic Form.
As is usual when swimming, the druid cannot drink or eat in this form.
Tips and tactics
Use this whenever you go into the water. It is a useful technique for escaping PvP opponents, as few can equal the Sea lion's swim speed and few can hold their breath long enough to catch you. However, without [Glyph of Aquatic Form] you are still slower than a hunter's pet underwater.
Be slightly wary of Warlocks underwater. They can breathe with a buff and their skills aren't restricted like the Aquatic form Druid's are.
[Azure Silk Belt]
[Glompmaw's Ring]
[Unending Breath]
[Hook of the Master Angler]
[Speedbarge Diving Helm] (swimming)
[Travel Form]
[Swim Speed Potion]
[Shimmerscale Diving Suit]
[Pocket-Sized Computation Device] via 
[Slipstream Generator]
[Sea Legs] (swimming)
[Underlight Angler] with 
[Underlight Blessing]
[Vashj'ir Seahorse]
[Hibernate] for instance).
[Glyph of Aquatic Form] you are still slower than a hunter's pet underwater.
Patch 7.0.3 (2016-07-19): Merged into 
Patch 5.0.4 (2012-08-28): Now costs 5% of base mana, down from 8%. 
Patch 4.0.1 (2010-10-12): Costs 8% of base mana, down from 13%. 
Patch 3.0.8 (2009-01-20): Aquatic Form is now available from druid trainers at level 16. 
Patch 1.6.0 (2005-07-12):
Patch 0.12 (2004-10-11):
