Avenger is a better revenge talisman than counter for magic dealers, stunners or buff stealers since it revenges when any ally is attacked. Horus can.be useful with avenger, he can revenge stun even if your opponents have angel talisman if they dont have immunity. A revenge stun can take away second turns even with angel, but with the new stop debuffs that is another option.

With all the blue buff stealers using talisman that give blue buffs is always problematic, especially in arena. PVE or even gauntlet is more reliable.

A good example of using avenger was on green troll in the current madness dungeon mission.