After the latest patch Barethiel often does not show his swing animation when he slays xenos with the hammer.
The sound plays, and the nids die, but he is just standing there in his normal pose. His shield isn't blocking nor is he doing one of his rest animations. He's just stiff there, then BOOM sound, dead xenos.
I'd say about 5-7 times out of 10 you see no swing animation.