cliché: baptism by fire

(also, baptism of fire)

Meaning: an ordeal, especially of martyrdom; soldier’s first battle experiences (definition).

Example: On his first day, the customer service rep faced a first rate consumer rage call, an epic baptism of fire.

Origins: First used in French to reference a soldier’s experience in battle, 1822. Also Biblical references. (Source.)

Rewrites:

• baptism by conflagration
• blessing by bayonet
• passion by ambush
• ecstasy by battle
• immersion by Armageddon
• purification by scrabble

Discussion: There are a couple of different ways to go with this idiom. Be inventive.