Trojan? is a side-scrolling action game produced by Capcom originally released as a coin operated video game in 1986. A home version for the Nintendo Entertainment System was released during the same year.

Set in a post-apocalyptic future during the aftermath of a nuclear war, the player takes control of a warrior who is hired to defeat the gang of an evil dictator. The hero is armed with a sword and shield, but has also been trained in the martial arts.[2] The arcade version can be played by up to two players alternating. The games controls consists of an eight-way joystick and two action buttons. Similarly to Kung-Fu Master or Rushn Attack, the player jumps by holding the joystick upwards instead of having a dedicated jump button like other side-scrolling action games. Instead, one button is used to swing the sword at enemies and the other button is used to hold the shield to block enemy attacks, including projectiles such as throwing knives and arrows. The shield can be held towards the player while standing or crouching, as well as upwards vertically and diagonally. Some enemies will throw magic balls which will cause the player to lose their sword and shield if they block. During these instances, the player will fight barehanded, with the sword and shield buttons used to punch and kick respectively. The sword and shield will appear on-screen after some point, allowing the player to recover their weapon. Other power-ups includes floating hearts that will restore the players health and jumping spots where the player can jump higher than usual.

The game consist of six stages, where the player will face the usual series of small fry enemies, as well as a sub-boss at the middle of each stage and a boss at the end. The player is allowed to start the game at any of the six stages. However, the player must play through the entire game again after defeating the final boss, Achilles, in order to see the true ending (similarly to Ghosts n Goblins). The player can continue after a game over depending on the dip switch settings.

The NES version of Trojan features several significant changes to the game, such as the addition of new power-ups and hidden rooms, as well as an alternative Versus Mode, where two players compete against each other in a best-two-out-of-three duel, making it Capcoms first attempt in the fighting game genre. Player 1 controls the main character, while Player 2 controls the enemy Trojan, whose abilities are identical to the main character.