Ikaruga is a vertical-scroll, shoot'em up video game developed by Treasure, originally for the Sega NAOMI in 2001 and was ported to the Nintendo Gamecube in 2003, and later the PC gaming platform Steam in 2014.
Ikaruga revolves around the two Hitekkai aircraft known as the Ikaruga and Ginkei, which are outfitted with weapons systems that can switch between the polarity of black and white projectiles to absorb them, which charges a secondary attack. Getting hit by the opposing projectile pellet color will destroy the ship. All of the enemies are either black or white, and hitting enemies with their opposite color does additional damage. There are three difficulty levels.
"Easy" All enemies that are destroyed do no release shots.
"Normal" Only enemies that match the players ship corresponding color release a burst of shots when destroyed.
"Hard" All enemies, regardless of color, will release a burst of shots when destroyed.
Despite their names, "Easy" and "Normal" modes can actually make the game more difficult in certain situations, because they reduce the number of dots that a player can absorb to charge their screen-clearing special attack.
Like its predecessor bullet-hell shooters Radiant Silvergun and Gunstar Heroes, the hitbox for the player's ship in Ikaruga does not encompass the player's entire ship and only exists at the ship's exact center. If an enemy projectile or ship makes contact with the center of player's ship, they lose a life. On each playthrough a player has three lives. Once these lives are depleted they must use a Continue if they wish to keep playing.
The player takes control of either ace pilots Shinra, piloting the Ikaruga, or Kagari, piloting the Ginkei, with little difference other than the appearance of their ship. The second player will take control of whichever ship was not chosen.