蛟龙得水jiāo lóng dé shuǐ

蛟龙欣逢雨水。喻指君主得民心；英雄逢时大有凭藉、施展之机。

例所谓蛟龙得水之秋，自此一举，此后不复与诸君伍矣。——《北史》

英to have an opportunity to bring one's ability into full play;