Vox is amazing for the Knull boss in this month's side quest. The reason is that you don't get power by hitting the opponent but rather by gaining buffs, and Vox gains a bunch of buffs. When he uses an SP3, he converts all of his current buffs into intensify buffs. This allows him to just loop SP3s back-to-back.
Disregard my failed intercept in the beginning. You need to land one in order to deactivate Knull's Protection, and I failed to.