敵

enemy fortress

error made by the enemy or opposing team

Shogi

opponent's king

benefitting the enemy; benefiting the enemy

encountering the enemy

enemy camp

formidable foe

language of the enemy (esp. English in Japan during WWII)

Video games

opponent's car (in racing games); rival driver

treacherous enemy

Shogi

opponent's rook; opponent's hisha

opponents pawn

daring; fearless; audacious; bold; dauntless; daredevil

hostile relations; hostile relationship

desertion in the face of the enemy; deserting under enemy fire

adversary; opposition; hostile forces

don't let your guard down; carelessness is the great enemy; danger comes soonest when it is despised

From Uesugi Kenshin sending salt to his enemy, Takeda Shingen, when Takeda's salt supply had been cut off

to save an enemy from trouble instead of taking advantage of their weakness; to show humanity even to one's enemy; to help one's enemy in difficulty

mortal enemy; sworn enemy; nemesis

hostile act

peerless; unequalled; unequaled

unbeatable; invincible; irresistible

hypothetical or imaginary enemy

act which serves the interests of (benefits) the enemy