Counter or counterattack is a passive ability that can be observed on the battlefield. Only a select few units possess this ability. Counter-attack allows a unit that just came under attack from an enemy to retaliate against this enemy straight away, before the next turn begins.
Counterattacks are range-dependent: a counterattack will not be triggered if it cannot reach the attacker's space. For instance, say, Griffin the Swordsman has a counterattack that can reach one space. He is hit with a Bow attack from three spaces away. He cannot reach the attacker, and thus will not counterattack.
Servants of Gods and Telepath Psy Arena 1 & 2[]
Counterattack are facing-dependent: characters will only counterattack if they enemy attack from the front.
Telepath Tactics[]
Counterattacks are not facing-dependent in Telepath Tactics, so a counterattack will result in the character automatically turning to face the attacker when counterattacking. A counterattack will not be triggered if it requires more energy than the would-be counterattacker has. Counterattacks are limited to certain number per turn. Once a character has used up all of his/her counterattacks, that character will not counterattack again until his/her counterattack counter is reset.