[Switchblade]

In cases where the show has more than two Riders, I usually assign the secondary Rider label to whichever character gets the most focus besides the protagonist. Garren was introduced first in Blade, for example, but Chalice gets far more development as a character and is more central to the main plot, which is why I consider him to be the secondary Rider of that series.

Gaim is kind of a weird show to call, though, as most of the major Riders are getting fairly even development. I want to say that Baron is the secondary Rider because he is definitely reminiscent of Knight and his role in Ryuki, but for a long time Ryugen was much more relevant and he still arguably plays the more important role in the story. The main difference, though, is that Micchy is pretty much an out-and-out villain by this point.