“...and we'll put you back in the dungeon forever."
The moment Thor finished speaking, Loki burst into laughter. Thor's eyes narrowed.
"You think this amusing, brother?"
Loki, who appeared to have somewhat gotten himself under control, replied, "sorry, it's just—it's been months since I've heard anything so stupid. I'm so sorry for making fun of your sense of humor; that's the best thing I've heard the whole time I've been in here." He chuckled, wiping tears from the corners of his eyes.
Thor's countenance didn't lighten one bit. To the contrary, his expression quickly became as stormy as his thunder. "Enough of this, Loki! Will you join us, or will you rot in here, alone?"
For a moment, Loki's face expressed genuine confusion. Then, like he'd heard that Odin had finally died because he tripped over a brick, gleeful mirth took its place, a grin spreading rapidly across his features. "Wait..." he breathed, "no—even you can't possibly be that stupid."
In direct contrast to his delighted brother, Thor sported a grimace indicative of the fact that his non-existent patience had worn thin. "My patience has worn thin!" He announced, albeit unnecessarily. "What is your answer?"
Loki began to succumb to further paroxysms of laughter, shoulders shaking as he gasped out a response.
"That's—oh my god—that—that's the worst possible way to convince anyone to do anything, ever!" He clutched the back of his chair, making a valiant effort to remain standing. It was a losing battle, and he quickly found himself on the floor, victim to his cachinnations, any and all previous efforts to remain serious (or vertical) abandoned. "And you actually thought that I'd join you? Oh my god Thor, you can't possibly think—oh, who am I kidding, of course you would. Here's a tip, brother," he offered magnanimously, altruistic appearance somewhat undermined by the fact that his entire body was shaking with glee, "when you want someone to do something for you, you should offer something in return. I know this may sound odd for you, but for civilized people, threats of death and imprisonment typically fall into the category of 'things that aren't going to get you anywhere in a negotiation.'"
Disregarding the fact that Thor looked angry enough to take on a helicarrier (partly because the comedic gold was too good to pass up, and partly because Thor's anger was like Mondays—annoying, but constant to the point where a lack thereof would incite mass panic), Loki continued dispensing advice.
"I know there's no way that you or the Allfather would keep up your end of the deal, but to not even pretend to offer one is just insulting. I'm hurt, brother. Deeply, irrevocably wounded."
One look at Loki's face would indicate that he was not, in fact hurt; to the contrary, rather, his appearance expressed a mood one would expect more from someone who'd just won the lottery while meeting Beyonce on Christmas day.
One look at Thor's would indicate that that had not been lost upon him, no matter how bereft he was in the department of perspicacity. Were one to endeavor to draw further assumptions, it wouldn't be unreasonable to think that maybe Thor didn't appreciate the advice his brother was so selflessly providing.
Giving the same amount of regard to Thor's feelings as he always had, Loki continued. "Now, of course, you'd never be able to persuade me to do something so obviously against my own best interests, but you still should've pretended that helping you would be better for me, because right now, that idea’s laughably ridiculous. To put this into perspective for you, as it is, my options are as follows:
"Option one: Come aid you on your suicidal quest that goes against the Allfather's orders, while putting up with you, your little mortal, and your gormless friends. I would be at great risk of personal harm, and—since you make it clear you don't trust me—most likely have my magic bound or whatever other idea you would come up with so that I wouldn't be able to fight you. Knowing you and the warriors four, you would treat me with such suspicion that I wouldn't be able to get things done anyway, not to mention the fact that your incompetence has been ruining my plans for centuries, even when you were part of them. And then, assuming we succeed in this impossible quest and I survive, my reward would be to be thrown into the dungeons again, to remain here while you go and party with your friends.
"Or option two: I don't help you, and you die along with all of your friends.
"In case it's unclear which situation I prefer, I think I'd rather take the route where you and everyone you love end up dead. Then, not only will you be unable to bother me anymore, you'll also be unable to keep me here in these dungeons. Oh, and you won't be able to prevent me from taking over Asgard, either."
With this, he finished, looking to his brother for a response.
"Wow," said Thor, looking shocked, "that's completely true and so obvious that even an idiot could see it." At this, Loki smirked, but refrained from commenting.
"I honestly don't know what came over me," continued the god of thunder, "I mean, I'm not the smartest person, but I've never done something so stupid before. That's such an inconsistency in my personality that if, say, everything I did were dictated by some sort of higher power, I'd wonder what the hell they were thinking."
"I agree," concurred Loki, "I mean, any being that stupid might've thought I'd actually accept that terrible deal! I'm sure glad that nothing like that actually exists and controls everything we do."
"That would be ridiculous," nodded Thor. "Anyway, we need you to come help us on this quest so I'm just gonna threaten you again in a more menacing voice and see if that changes anything this time."
"Sounds like a wonderful idea Thor. Simply marvelous."