The ESRB rated Rygar (arcade) and Ninja Gaiden (arcade) for Wii, identifying both titles as Virtual Console arcade games. The NES version of Ninja Gaiden has been online since 2007, but the arcade game is quite different. It has co-op play and a hilarious title screen.
And for more amusement read these ESRB descriptions for Rygar and Ninja Gaiden.
Ninja Gaiden — rated E10+
This is an arcade-style action game in which players assume the role of a ninja who fights his way through a 2D side-scrolling environment. Players punch, kick, and use swords to slash at street thugs carrying batons and blades. Occasional boss battles require players to attack stronger enemies in more protracted battle. When players lose all their “lives,” a “Game Over” screen depicts a circular saw being lowered down on the central character as the screen fades to red. In one area of the game, a background mural shows a man in a tight-fitting leather outfit that exposes portions of his buttocks. Some billboards and signs display the word beer.
Rygar — rated E10+
This is an arcade-style action game in which players fight their way through 2D side-scrolling environments to earn points and achieve the highest score. Players can punch demons, dragons, lava creatures, and large birds, or use a projectile-chain weapon to defeat them. Enemies react to damage by dissolving in a red-and-white burst of bones. In one level, there are small animal skulls in the background.