I was doing the spawn in Cove with my bard, and we killed the vanguard. The horse was just sitting there so we decided to kill it. when it got down to a quarter life it did the special attack where the black smoke comes out from under neath it. My resist on my bard is crappy and it took me down to 3/4 life and poisoned me. I had to cure twice for it to take affect. The warrior got poisoned and it took about 1/4 of his hit points. It was a surprise because I wasn't expecting it.