King Of Fighters 2003 Play as Adelheid
Reach Kusanagi and defeat him with a normal move in arcade mode. Then, defeat Adelheid in the final Boss battle. Next, highlight Iori at the character selection screen and hold R1.
Play as Mukai
Reach Kusanagi and defeat him using a DM move in arcade mode. Then, defeat Mukai in the final Boss battle. Next, highlight Kyo at the character selection screen and hold R1.
Gallery items
Win one round of S-Survival (single) mode against each character to unlock individual character art in the gallery menu. Win one round of T-Survival (team) mode against each team to unlock the team ending sequences in the gallery. Note: Defeating Kyo, Chizuru, Adel and Mukai will unlock the usual intermission sequences that occur before and after fighting them.