an experimental build around gas damage:

in theory, viral damage works best when you can sustain damage to a target, which isn't always the case with bows: draw time, constant reload, and difficult aiming can make it a challenge. plus, on bows like the [Paris], viral would only affect one enemy at a time if you WERE going for sustained damage

ideally, gas damage allows you to hit an enemy once, and let it proc for a while while you prepare the next shot. in addition, you can aim for the center of the crowd for crowd control when you aren't aiming for one main enemy