- Not available on that edition (the reason is in the tooltip)
- Depends on the setting, your class or another addon (details in the tooltip)
What it does
Checks if the unit specified is in combat.
Why you might use it
Checks whether a unit is in combat. On yourself, NOT COMBAT gives you out-of-combat steps such as raid buffs, poisons, weapon imbues or summoning a pet before the pull, and it can switch to a separate out-of-combat rotation. On your target, it can keep you from opening on something that has not been pulled yet. See also Time Since Combat Start.
Example
you are in combat
Settings
What each setting in the condition editor means, from the game's own help.
Unit - The unit this condition uses as the target of comparison.