Enemy Shamans are typically protected by a magical barrier. To damage them, you must first destroy the small ritual pillars or totems surrounding them.
They do not fight directly but continuously summon regular Legion soldiers to swarm you. Battle Strategy: viking-battle-for-asgard-prophet
Use Dragon Runes to call in dragon air strikes (like Ari or Kelda) to clear the pillars and barriers instantly, making the Shaman vulnerable to a standard finishing blow. Enemy Shamans are typically protected by a magical barrier
Once their barrier is down, a standard slash is often faster than performing a long fatality move. Critical Shaman Locations & Rewards Viking: Battle For Asgard Playthrough | Part 1 viking-battle-for-asgard-prophet