One Who Runs Purple_Dave: This character probably wins the prize for Most Obscure Buildable MATORAN. There is only one place that I've ever seen him, and I suspect he might have been intended to be KAPURA due to how small of an appearance he puts in. Since he appears in one of the movies, he's actually only around for about two seconds. If you want to see for yourself, go here. Notice that KAPURA is present in the early part of the movie, but the only MATORAN with a PAKARI who runs forward has yellow legs like JALA and the twin guards.
Anyways, to build him yourself, you just need to swap JALA's mask with a red PAKARI.