All-Star Battle/Koichi Hirose

Koichi makes his playable debut in the PS3 game and was confirmed along with Akira Otoshi. Koichi is voiced by Romi Park, who previously voiced Giorno Giovanna and Gold Experience Requiem in the aforementioned PS2 GioGio game.

As one of the majority of playable characters with the "Stand" Style, Koichi can turn Echoes ACT3 on/off, changing movesets, as well as having access to the Stand Rush ability returning from the Capcom game, being able to attack in conjunction with his Stand. Along with Enrico Pucci, Kosaku-Kira, Johnny Joestar, Hol Horse, and Giorno Giovanna, Koichi is a character who can utilize more than one Stand during a match as part of his moveset. In gameplay, Koichi uses all three forms of Echoes as part of his moveset, unlike Johnny or Pucci, who need to evolve their Stands during combat. Koichi has 900 HP.

Command List
During a fight, Koichi can use several different abilities that were featured in Diamond is Unbreakable.

Gameplay Overview
Koichi is an unorthodox fighter who can wield Echoes' unusual array of powers for a variety of scenarios. Due to his notably small stature (bested only by Iggy as the smallest character), he can play highly evasively and avoid his opponent's attacks with ease. Juxtaposing this is his long-reaching normal attacks and skills that can extend far away from him, allowing Koichi to apply offensive pressure at mid-range. His skills when utilizing ACT1 and ACT2 focus on crude utility, offering more diverse specials to play defensively or in skirmishes. Meanwhile, ACT3's abilities are more simplistic and emphasize a close-ranged offensive playstyle, with the threat of 3 Freeze being a valuable tool as well as an readily available, if not punishing combo breaker.

Koichi's weaknesses come in his small size and the fluidity of his arsenal. His size makes him easier to juggle and thus combo, coupled with lower-than-average health can render him vulnerable to heavy damage. A rare negative quality of his is that his set of skills, while fine individually, lack cohesion. Koichi's moves seldom flow well into each other on offense, possessing poor 'hitstun' or launching effects unsuited for use in combos. This results in him being a rather awkward character who is more limited in combo potential and damage output than most.

In all, Koichi aims to play around his opponent's attacks, using his small size yet large attacks to outmaneuver and punish mistakes accordingly. While in effective range to use ACT3's strength, he can apply 3 Freeze to force the opponent on the defensive, opening up opportunities to freely assault them with little chance of them retaliating.

Trivia

 * Koichi won the first place in his League Group in the All-Star Battle League, beating fan favorites such as Giorno, Jolyne, and Gyro. He even managed to reach to the semi-finals matches, but ultimately lost to Jotaro.