Take damage in place of an ally and counter attack.
Cover Counter (ぼうげき, Bōgeki?, lit. Defender) is an ability unique to Yang in Final Fantasy IV: The After Years. It is a combination of Cover and Counter where he gets a free counter-attack against an enemy who attacks the person he chooses to cover (or any other allies in HP Critical state), both taking damage. Cover Counter has a Charge Time of 0.
Cease Cover removes the Cover status and places Yang into Defend until his next turn comes up. Cease Cover has a Charge Time of 0.
The same or similar effect can be gained in other games by equipping Cover and Counter as support abilities to the same person.