Use an Ability
A player is considered to have used an ability when that ability is completed on a card they control. To be considered used, the ability must complete, meaning it cannot be prevented or affected by an instead modifier.
An optional ability (usually indicated by "may") is not considered completed if the controlling player chooses not to activate it, but it is considered completed if they either choose to activate it or if it is not optional.
An ability is considered used if it completes, even if there is no effect or if the effect involves other players.
A number of cards refer to 'Using' an ability - This section has been added to clarify what that means.
