Wait a second? Rhyhorn?! It's a Rhydon, I don't have a Rhyhorn anymore o.O Can you fix that please?

Aoshi: Start off with an attract of your own on Pikachu. With your superior speed, you should easily get your attract in before Pikachu does. Then start bouncing around the arena with Agility, keeping away from Poliwrath, Poliwrath would be too slow to get to you with it's Focus Punch, and it's unlikely Pikachu's Thunderwave could hit either. While Poliwrath's busy trying to grab Rhydon with Psychic, hit it with Toxic.

Attract (Pikachu) ~ Agility ~ Toxic (Poliwrath)

Matrix: Start off by quickly making a substitute, hopefully before Poliwrath can attract you too much. Then hit Pikachu with your best Hyper Beam. Your substitute should protect you against these attacks, since Psychic won't do any damage because it's not being slammed against anything, so retaliate with a Dynamicpunch on Pikachu, be sure not to be in the path of Pikachu's Dynamicpunch though.

Substitute ~ Hyper Beam (Pikachu) ~ Dynamicpunch (Pikachu)