Author's note: The only excuse for this story is that it's a joke that took on a life of its own. Originally, it was a short one-shot meant solely as a parody of all those stories where Harry develops an array of astonishing magical powers over the summer holidays and then blasts Voldemort out of the water without even breaking a sweat. (Reader check: I'm not the only one who's annoyed by those, right?) However, as it developed that none of my readers cared about my attempt at satire, but a great many liked the idea of a wizard Green Lantern, I decided to repost and go with Plan B: a whimsical look at what the Harry Potter cast would look like as the JLA. This is the result. Enjoy.

Disclaimer: If I owned Harry Potter, I wouldn't own DC Comics. If I owned DC Comics, I wouldn't own Harry Potter. As it is, I own neither.

All right, let's see, Harry Potter thought to himself as he wandered about the empty Quidditch field. Katie's looking good, so is Demelza; Ginny's looking… He flushed in spite of himself. …well, yes, all right, Ginny's looking very good; and Peakes and Coote seem to be handling things all right. If it weren't for Ron's nerves, we'd be in great sha…

But before he could think the final phoneme, something extraordinary happened. A bright green light, which seemed to come out of nowhere, surrounded him and lifted him off the ground; before he knew quite what was happening, it had carried him away from Hogwarts and was sending him soaring across the British countryside.

Instinctively, he reached for his wand. What's going on? he thought. Is Voldemort up to something? Green's his colour, all right… but, if this is Dark magic, how did it get past the defences at Hogwarts?

Before he could come to a satisfactory conclusion, the light abruptly vanished, and he dropped out of the air onto a desolate strip of Cornish coastline. He glanced around, and realised to his astonishment that he was standing not five yards from a crashed alien spaceship.

«Come in, Harry Potter,» said a voice in his head.

Bewildered but obedient, he stepped toward the spaceship and clambered awkwardly through a dome-shaped opening. Inside the spaceship, prone on the floor of the control room, lay a magenta-skinned alien in a strange green uniform.

«I am Abin Sur,» said the voice in Harry's head. «I am not of Earth, but of a far distant world – and I am dying.»

"Um... I'm sorry, sir," said Harry awkwardly.

Abin Sur shook his head. «It is unimportant now,» he said. «I have rid the universe of a foul and malevolent entity; if in the process I have sacrificed my life, there are worse ways to die. So long as I have a successor…»

"A successor, sir?" said Harry.

«Yes,» said Abin Sur. He raised his hand, and Harry saw that his middle finger held a green ring, which seemed to glow with the same sort of light that had surrounded him a few minutes before. «This is the power that brought you here; it is an energy beam that can assume any shape, or perform any task, that I desire of it. With this power, I and a few thousand others around the universe carry out a perpetual battle against the forces of evil and injustice.

«When I realised that I was dying, I had the beam search this planet for a mind that was both honest and fearless. That is how you, Harry Potter, come to be here: the ring has chosen you as its next bearer. Take it, please, for time is short – and take also the object like a green lantern on the platform above me, for it is from that that the ring draws its power. Every twenty-four of your Earth hours, you must place the ring against the battery and recite the following oath…»

Harry coughed. "Er… excuse me, Mr Sur," he said. "I'm sorry to have to disappoint you, but I can't accept this power."

Abin Sur smiled. «I understand,» he said. «When I was chosen, I too felt unworthy. But be at ease, Harry Potter; the ring does not err in such matters. If it has chosen you…»

Harry shook his head. "No, that's not what I mean," he said. "You see, about a week ago, I was serving detention with Professor Snape when a lightning bolt hit the Potions classroom. A whole bunch of potion ingredients spilled over me, and, when I regained consciousness, I discovered that I had been put in contact with the Speed Force."

Abin Sur frowned. «Indeed?»

"'Fraid so," said Harry. "I've even commissioned a red bodysuit with wings on the feet from Madam Malkin's. So you see, I already have commitments."

«Ah,» said Abin Sur. «Well, in that case, do you know a person named…» He paused, and glanced down at the image that was forming inside his ring. «…"Luna Lovegood"?»