A surprise attack; striking suddenly before the opponent is prepared (used in military or competitive contexts).
敵は夜間に奇襲をかけてきた。
The enemy launched a surprise attack at night.
奇襲によって補給線が断たれた。
The supply lines were cut off by a surprise attack.
相手チームは奇襲攻撃でリードを奪った。
The opposing team took the lead with a surprise attack.