Rev up the speculation engines, because this teaser is just that: a giant tease for Empath, a new hero coming February 4, 2011. While @S2Nome also provided a thread showing off her ability icons, there’s very little that can be confirmed by just watching the video. And S2 is being very quiet about the abilities on the forums. She has five ability icons, meaning that Staff of the Master will no doubt augment her ultimate to add a fifth ability — similar to Nymphora.
You can actually glean a little information from the teaser. For one, her ultimate attaches her to a target — presumably just allies — and has what looks to be a beneficial effect on the hero. I’m going to go ahead and guess that she shares the damage they take — transferring some of it from the ally to her. She can also obviously cast while attached to a hero, as you can see her use the “W” ability after attaching herself to Rampage.
“Q” looks to be a heal, though that’s harder to guess. I can’t see a point during the match where she uses it, unless it’s a heal-over-time and that’s what causes the green glow while she’s attached to Rampage. In that case, perhaps her ultimate actually grants magic immunity. Or maybe that’s the “E” ability. Who knows. “W” on the other hand, is fairly cut-and-dry. She can create an impassible barrier on the map, preventing enemies from getting away in the event of a chase. Based on comments by Nome on Twitter, “W” used to be her ultimate — at least part of her old ultimate, anyway.
At any rate, I can see why she required special code for some of her abilities. Nome alluded to the fact that aspects of her were impossible in DotA, and I’m going to guess her ultimate is one of them.