General Synonyms:
* Surprise attack
* Raid
* 伏擊 (fú jī) (Chinese) - literally translates to "to ambush"
* 突襲 (tū xí) (Chinese) - literally translates to "sudden attack"
More Specific Synonyms:
* Trap - implies a more planned and deliberate setup.
* Snipe - specifically refers to a surprise attack from a hidden location using a sniper rifle.
* 伏兵 (fú bīng) (Chinese) - literally translates to "hidden troops"
* 埋伏 (mái fú) (Chinese) - literally translates to "to lie in ambush"
The best synonym for "ambush" will depend on the specific situation and the desired nuance.