Alternative form of what doesn't kill you makes you stronger

Hardship builds moral character.

Alternative form of keys to the kingdom

Alternative form of kit and caboodle

(figuratively) To dance. / (idiomatic) To relax; to enjoy oneself; to do as one pleases. / Used other than figuratively or idiomatically: see kick, up, one's, heels.

Used other than figuratively or idiomatically: see kick, heels. / (idiomatic) To wait; to wait impatiently or restlessly.

Anthyllis vulneraria, a medical plant in the pea family

(UK, dated, informal) To rebel against authority; to defy orders or instructions. / (UK, dated, informal) To live overextravagantly; to come to grief by fast living.

(idiomatic) A humiliating insult or instance of bad treatment, especially when one is expecting friendship or in need of support; a sudden and unexpected setback; a strong rebuff.

a person who commits mercy killing