Proof that appearances can be deceptive, Rufus has one of the best - and quickest - special moves in the game.
It's simple enough but his dive kick (down/towards + MK when in the air) brings him close to his opponent and is extremely hard to hit on reaction, meaning it's easy for Rufus to gain momentum and annoy his opponent.
Which is just as well because while he's built like a combo machine, Rufus struggles when he's having to defend himself. So keep the momentum up and land those combos!
Messiah Kick (quarter-circle towards + K, K)
The first kick sees Rufus spins towards his opponent, setting up his second kick. If you press LK, he goes for a launcher. If you press MK, he goes for a slide. If you press HK, he goes for an overhead. The launcher is the one you want to land but remember to mix in the other options. Sometimes, don't do the second kick and walk in and throw (or charge a Focus Attack), just to ensure your opponents never get too comfortable. The EX version is almost unstoppable due to its speed...
Galactic Tornado (quarter-circle towards + P)
Rufus spins then hits the opponent away. It's a good move for setting up his Ultra and for ending combos though the range and timing on cancelling HP into Galactic Tornado is quite fussy.
Snake Strike (towards, down, down/towards + P)
Rufus jumps upwards stabbing at the air with his fists. It looks like an anti-air move but works better after you've hit them upwards, such as with LK > HK on the ground or an air-to-air HK. The EX version comes out faster and does more damage.
Spectacle Romance (quarter-circle towards, quarter-circle towards + P)
Hardly ever used because you want to burn EX meter on Messiah Kick instead.
Space Opera Symphony (quarter-circle towards, quarter-circle towards + PPP)
An annoying Ultra as it combos off almost everything Rufus does - LK > HK, Galactic Tornado, air-to-air HK... learn all the set-ups and then keep this Ultra in check until you can use it as part of a combo. Never randomly throw it out there, as it will be a waste of an Ultra if you do so.
Basic Combo: LK > HK > Snake Strike
Advanced Combo: (air) down/towards + MK > LK > HK > Space Opera Symphony