The team up fights. Team up with your mentor to face their arch enemy. And it is GLORIOUS.
Kicking Powergirl's butt in the first episode of the Legacy of Krypton arc.
In the first Batman mission against Scarecrow, the boss fight against him consists of fighting many fear based hallucinations. Suddenly, when he prepares to unleash his next swarm... he discovers he's ran out of fear gas. Indeed, you have just proven you don't fear ANYTHING.
The ending movie for the Bludhaven alert. Nightwing is crushed over the fate of his city... but as he says, he's stronger now that he's learned to get back up and continue fighting.