Good voice acting, timing, art direction, and writing. Since you asked for constructive criticism, I think you could have made the characters visually emote a bit more in the opening conversation (Move their irises and eyebrows more, gesture with their arms), and the barbarian's lean at the 1-minute mark made his model look a little overly slanted - if you're using software that supports it, I'd look into better incorporating layer rotation for that kind of stuff. It'll be neat to see more of this!