Rygar: The Battle of Argus is an action title, plain and simple. The basic gameplay mechanic is to beat the crap out of anything that moves. Ryagr is a gladiator that has lost his memory and quickly becomes the chosen one to wield the legendary weapon, the Diskarmor, to save Princess Harmonia who has been kidnapped by evil demons. Fighting with the yo-yo like Diskarmor is legitimately fun and combat stays engaging all the way to the end, but the pacing is all over the place and takes away from the enjoyment.
At the very beginning of Rygar: The Battle of Argus, you acquire the fabled Diskarmor and fight your way through a few rooms underneath a coliseum and then you encounter the first boss battle. So far, so good. The next few levels are full of puzzles and low level enemies until you get your first permanent upgrade to your weapon. Unfortunately, your upgrade comes with a boss fight and then another upgrade immediately afterwards, which means another boss fight.
I wouldn't bring this up if it weren't for the fact that Rygar: The Battle of Argus still uses an archaic save system without any checkpoints. So, if you make your way through the first two bosses and die on the third, you have to start all over again from wherever you last saved.
Even the most basic action titles today at least have a checkpoint system so that you can start from the most recent area, and not over a half hour's worth of progress away. It just feeds into the main problem that the developers did not add anything to update Rygar to compete with today's market.
Well, that isn't entirely true, they did add a new gameplay mode called "Gladiator Mode" which makes you fight level after level of enemies until a boss fight, and then fight some more enemies. It is basically a survival mode, but with a very specific twist. The only way to attack with the Diskarmor is to use the motions of the Wii-mote. Throughout the main game, combat is mainly on the face buttons with a few strong attacks that can be charged by shaking the Wii-mote. In "Gladiator Mode," all of the combat is based on shaking the Wii-mote. It can tell which direction you are swinging which corresponds to a different attack. It also knows how hard you are swinging each time. So, what it boils down to is how fast and hard can you swing your arms in order to clear the rooms before you die or run out of time. If you want to consider how tired my arms were afterwards a good thing for kids to get active in their games, then go ahead. I didn't think it was smart or fun, I just found it useless and tiresome.
I have read that some people are being unfairly cruel to Rygar: The Battle of Argus simply because it didn't do anything new. Well, while that is a very valid reason to complain, you also have to consider that is only 7 years old and for the time, nearly everything it did well would be used in other games later on. So what was new in 2002 is now a reference list for what most people don't want action games to do in 2009.
It has on-the-fly weapon switching. It has big, huge boss battles accompanied with an epic world to explore. It had traversal mechanics that I don't remember anyone else doing until Ratchet and Clank or God of War But for everything it did right, it still had rooms that would seal off until all of the enemies were cleared. It also had aggravating platforming elements, enemies that would attack from off-screen, and serious health management problems. But I think the good just slightly nudges out the bad in this case.