Battle Stadium D.O.N (バトルスタジアムＤＯＮ) is a Japanese fighting game featuring characters from the three popular manga series published by Weekly Shōnen Jump: Dragon Ball Z, One Piece, and Naruto -- D.O.N.
Similar to the Super Smash Bros. series, the players are put onto either a moving or non-moving stage. Like Power Stone, these stages have some level of interactivity. Players must then fight their opponents. Unlike other fighters, D.O.N uses a combined health gauge, that is, decreasing the health of one player will in turn increase the health of the other players. Thus, in order for one player to win a fight, they must make their own health bar take up the entire bar. As such, a fight can potentially last indefinitely if no time limit is set. Also, there are in-game techniques that can be pulled off (i.e. Kamehameha for Goku and Summoning Jutsu for Naruto) and supers that can transform the characters into a new form (i.e. Naruto's Rasengan turning him into the Kyuubi and Goku's Genki Dama turning him into Super Saiyan). In addition, some characters can induce a temporary transformation during the battle (i.e. Sasuke's Sharingan and Luffy's Gear 2nd).
The single player mode has the player fight through five rounds, 2 or 3 of which have missions with goals selected randomly. However, depending on the difficulty chosen by the player, different amounts of missions are given out with easy giving the least and very difficult giving out the most. Fulfilling the missions' goals rewards the player with coins that can be used in the slot machine available upon completing the fights. The slot machine is the way through which unlockables are obtained.
Up to four players can participate in a multiplayer session, though a multitap must be used for more than two players for the PS2 version.
Source: Wikipedia, "Battle Stadium D.O.N", available under the CC-BY-SA License.