Finally managed to find and fight Red Rider, and...kinda disappointed, since I beat him on my first try. To be fair, though, I got lucky with him never using or getting to use Antichthon. I read that you can get away with bringing at least two demons that null, repel, or drain fire, so I kept Uriel and Michael around for that, with Seth set for my fourth demon without any fire protection (I only brought him since mine had Doping, but I completely forgot my Michael had it too), then swapped out Seth for Demonee-ho on my second turn, who only resists fire. The only real problems I ran into were War Cry and Purple Smoke (along with a critical with one regular attack), but I had Flynn deal with the latter with Salvation and the former with a Dekunda Stone by the time I had my Uriel w/Dark Energy+Charge ready, using Demonee-ho to hit Red Rider's ice weakness with Breath (having had Michael use Archangel's Law on him for that on the third turn), with Flynn also hitting him with Antichthon a couple of times during the fight. By the fourth turn, I had my chance for Kannuki-Throw with a smirking Uriel, so I went for it and that was it.
That said, even if I didn't have something as overpowered as the same Uriel that I used to beat Masakado's Shadow on my team, I didn't consider it a particularly difficult fight based on how things were going for me. I wanted to beat the crap out of Red Rider after all of the trouble I went through to finally get him to show up, but I'd be lying if said Kannuki-Throw+Dark Energy+Charge+Smirk didn't take some of the fun out of it, as cathartic as it was to see.