Yippie-ki-yay!
In Spinmaster, known in Japan as Miracle Adventure (ミラクルアドベンチャー), you play as Johnny and Tom, two treasure seekers. They have to save Johnny's girlfriend and gather map pieces in order to find the biggest treasure in the world! Along the way, they must fight past lots of quirky henchmen, large bosses, and more, all accompanied by cartoony graphics and stereotypical cowboy voice clips.
In this game, Johnny and Tom can use several different types of weapons, such as the elements of ice, fire, and thunder. They can collect a limited number of super attacks, denoted by the letter "B" under their health bars, to hurt everything on the screen and damage bosses heavily. Also, health does not refill between levels.
If you want to see another Arcade game involving two treasure hunters fighting lots of enemies, be sure to check out x2poet's run of Top Hunter: Roddy & Cathy.