@ubi-woofer My issue is not the exact same. I was able to defend the shield against the attack, but the quest never continued after that. I left Asgard and now the builder is nowhere to be found. The shield appears to do nothing. It doesn't do any damage to me or the enemies. I am playing on PC and would share a save file, but I cannot find it. The FAQ says there should be a Saves folder in the Assassin's Creed Valhalla folder in Documents, but there is not one there.