Cooldown

Cooldown is a keyword and means an interval to the next use, and is counted in seconds. The next use can be performed after cooldown time passes, except when there are stored uses.

Mechanic

Cooldown usually starts after first action of using skill known as cast time, but there could be exceptions. If cast time is 1 second and cooldown is 4 seconds the next use of skill can be started after 5 seconds.

Certain skills will begin its cooldown when the effect expires instead of after cast time end (Ex. all Guard skills, Withering Step).

If there are stored uses, cooldown stacks after consuming uses of skill and do not overlap. Example: skill has 3 uses, cooldown is 8 seconds, then all uses can be consumed on demand, for example in 3 seconds. Cooldown stacks and each use of skill will be recovered after each cooldown ends. In other words, all 3 uses will be recovered after all 3 cooldowns end, after 24 seconds (3 x 8 second), since start first cooldown.

The cooldown can be bypassed by specific mechanics depending on the skill e.g. Cold Snap and Flicker Strike's cooldown can be bypassed by consuming a Frenzy Charge.

Cooldown time can be changed with different sources of Cooldown Recovery Rate. Cooldown Recovery Rate changes the rate of cooldowns recovering, not the cooldown timer. For example, a 50% increased Cooldown Recovery Speed on a skill on a 6 second cooldown will change the cooldown period to 4 seconds (6 / (1 + 0.5)), not 3 seconds (6 * (1 - 0.5)).

Vaal skills have a property where changes to duration (for Vaal skills with the "Duration" tag) also changes the cooldown period of the skill.