A/N: Based on a Forces prompt.
He spends most of his time whistling aimless tunes that tick the doc off. Truth be told, most everything ticks the doc off these days. Matter of fact, it'd be easier to list the things that don't make Eggman's complexion turn an unhealthy shade of red (which amount to a meager total of seven, by the way), but he doesn't really care about the damage the whistling will cause him. He needs to fill this stark electric hum haunting his cell, and his racing thoughts aren't being much help in that department.
"I know what you're trying to do."
"Yeah? So didja come all the way down here just to tell me what a good job I'm doin'?"
"Don't play coy with me. You've been trying to make a fool of me in my own base."
"Gee, doc, whatever gave you that impression?"
Sonic employs a different whistle for each change of the guard. Sometimes it's fragments of the last rock song he heard on the radio. Other times, just to mix up his pitches, he mimics birdcall. Eggman especially hates it whenever he switches to bluejay.
Ten percent of the globe shines red from a holographic map. He can see it if he presses his cheek to the cold stone of his cell wall and squints from an angle. Today it grows a sliver, now eleven percent. It doesn't seem so bad until he remembers the forests of Mazuri constitute an eighth of the world, and Eggman's conquered a landmass slightly bigger than that.
"Listen to me, hedgehog, and listen carefully, because I'm only going to say this once. Once the Tower finishes construction, you're going to see the true extent of my power. This blue sliver is nothing, less than a speck. You see that map? All of it mine—"
"Then luckily for you, my constant thorn in my side, there will be no more need for you to be here. No longer chained up in this nasty little cell, how about that? You could be free."
" … Define 'free.'"
Sonic gets a bit lonely sometimes.
"Hey, Shadow, how's being a lapdog treatin' ya so far? You get a nice warm bed in this pretty sweet package deal? Fed three times a day?" As Shadow glares through the bars (with his strange eyes lacking light) he throws up his shackled hands. "Hey, nothin' goin', buddy. He doesn't even feed me that much."
"Yo, Metal, talk to me. What's the hot new robot gossip?"
More hours pass.
"Anyone got a clue when dinner's gonna be? C'mon, I can't be the only guy who wants to know around here."
Even more hours still. Heckling the guards eventually relents to a fitful sleep where Tails is still calling out his name.
Rinse, lather, repeat. This crushing tedium is enough to drive the hardiest person mad, but he knows that's exactly what Eggman wants: for him to crack under the strain of the one thing he hates most.
"Now, now, no need for us to quibble over terminology."
"Actually, Eggman, I'd rather we would."
"My point stands. How'd you like a nice change of scenery? Preferably in the cold, unforgiving reaches of space?"
"Oh no," Sonic deadpans, wiggling his fingers in mock fright, "not the timeout corner."
By the beginning of the third month, the map breaks fifty percent.
Will somebody shut him up? Eggman's shout echoes down the corridor. For Pete's sake, I can barely hear myself think over here!
Most of his thoughts are insignificant chatter, so he doesn't necessarily disagree, but there are a few rough gems hidden in there. As Zavok slumbers in front of his cell, he has the idle thought that he'd kill for a chili dog and a malt shake, but also that Amy loves picnics and if—no, when—he gets out of here, he'll take her to see some cherry blossoms sometime.
Life goes on. Slowly but surely the map grows its neon red blot. Eggman works himself into burnout. Once, he catches cold and orders Sonic to shut his big mouth about it, even though he's said nothing to inflame him. He hears the sneeze muffled behind thick concrete. It's not funny, you rodent! I didn't say anything. You wanted to! You're off your rocker, Egghead.
Sixty-three percent. This particular dot resists the tidal waves closing in before crimson swallows it. Another city falls. He closes his eyes.
Eggman sneezes as it burns, more forgotten than the handkerchief tucked in his back pocket.
Must be allergies, he insists, wrinkling his nose.
Progress jumps in fits and starts. Sixty-eight percent. Seventy. Eighty-two. Eighty-one. His heart catches in his throat. Eighty-five; a city in Spagonia struggles to maintain control of its defense systems.
Sonic tells his adventures to the walls, bars of fluorescent light crossing his cell in flickering beams. In his dreams he runs through endless fields. The sky wide open, the sun bearing down in all its glory, warming his wind-bathed fur as his steps carry him out of this world.
He'll find a way out of here. Exploit a hole in the system.
Soon he dreams of cities on fire, trees with metallic masks.
Tails is crying and he can't comfort him.
Sonic wishes there's a whistle to cure insomnia.
"I find it strange your friends haven't come calling for you," Eggman says one day, when Sonic is lying on his back with his legs propped against the wall.
He drops his arms with a groan. "Aw, heck, doc, I'm way too pooped for this. Ain'tcha got better things to do?"
"How lucky for you! It's my day off."
"Whoo-hoo," Sonic mutters. Then flips over onto his stomach. "Can I ask you something?"
Doc never passes up a chance to blabber on about himself, so of course he allows the indulgence.
"So what's your game plan here? What's gonna happen when you conquer all that," he gestures to the map, "and I'm gone, huh? You gonna move on? Conquer some other planets? Maybe try the moon again?"
"I'd well advise you not to mock me, Sonic."
"No, seriously, I wanna know. What're you going to do? Because I'll be pushin' up daisies, and by then you'll have to keep moving down the list, right? Check off all your boxes till it's just you and the big cheese. But I keep thinkin', y'know, you get bored awful easy—"
Eggman lunges forth and grips the bars. "Just what are you implying?"
"Why do you do it?" Sonic pushes himself into a stand by shimmying his back up the wall, no hands, of course, seeing how he had to teach himself. "Why go to all that trouble if you know you're just gonna get bored with it?" He throws up his cuffed hands before the doc can protest. "Yeah, yeah, world needs to know you're great and all that, I got the memo. But—why?"
"You want to know why?" Eggman asks. "Very well, I'll tell you why. Because once upon a time, a very gifted man was wrongfully executed, and the only progeny he left behind was laughed out of his own country for believing in things too 'far-fetched' for any 'respectable scientist' to prove. They thought I was a hack, that I would never amount to anything worthy of a pulp magazine cover, let alone my grandfather's name. But it is my name now, Sonic, and mine alone. Just look at this magnificence!" He sweeps his arms to encompass the base, and seems, indeed, to try to cradle the very universe on his shoulders. "See these exquisite machines and tell me they're not the work of the greatest scientific mind this world will ever produce!"
"Why do you have to prove it to me?" Sonic asks. "I'm not the one who laughed at you."
A crack in the veneer. "Wrong. You've been laughing at me since the day we met."
"You wanna know what I think, Egghead?"
"You need an audience." There. He reveals his hand. "This world-conquering stuff, it's just a way to get those people who laughed at you to applaud, or at least rub their noses in it. But you can't control what anyone thinks of you, so you have to get them to worship you, and it drives you nuts knowin' you can't do either." He grips the bars himself, intent on getting his two cents in before doc can shoot him down. "I think you try to control these monsters and Finny-boy because you can't control yourself or anyone else. And I think, Eggman, you keep me locked up here to remind yourself you haven't lost your mind. 'cause you do, and I'm deader than doornails. And you can't have that, not yet—"
Laughter explodes in his face. "Have nothing better to do than play armchair therapist now, Sonic? What do you think you know about me? That because you spend a little time languishing in one of my cells, you've got me all sorted out? The teenaged rat who can't sit still long enough to pay attention to a rudimentary science lecture is going to lecture me on self-control? Ha!"
"Self-control is leaving Shadow alone," Sonic shouts, "self-control is knowing to stop when you're ahead! You know what's not self-control? Waking up a different freaking monster every month!"
Eggman gets close, dangerously so, that for a moment Sonic believes he might slap him. "You'd better watch where you step those oversized feet, boy. Lecture me all you want, but there's no denying you wouldn't be here were it not for your selfish impulse to play hero. What do you think happened to Tails when you left? That's right, he ditched the Resistance. Left them high and dry just like his idol would have. Because when you get down to it, Sonic, you're nothing but a self-righteous hypocrite—"
"Better a hypocrite than a big fat impostor!"
Sonic ducks into the cell, avoiding the kick Eggman drives toward his head. The bars scream at impact and doc realizes he's royally messed up his foot for no good reason. He reels back a few steps, and Sonic seizes the opportunity to force him down by smashing his own foot through the bars into his vulnerable kneecap. The move draws a livid string of curses from the fat man as he staggers to recover his footing.
Sonic shakes the bars, these stupid things keeping him down—
"You wanna fight? Fine, then! Get in here and let's duke it out, buddy boy! Or is that gonna screw up your big plans? C'mon, king of the world, let's see you beat me with your own two hands! Can't do it, huh? I don't know but I'd like to see you try!"
He wants him transferred to the Imperial Tower effective immediately.
When he overhears this bit of news, he finds himself caught between grimness and laughter. Imperial Tower? Well, that settles it, Eggman's officially lost his one and only marble. There they'll probably expect him to sink onto one knee before His Majesty and kiss the ring. Gross.
Will he? Won't he? The uncertainty clouds his mind. Schrodinger's Sonic: both dead and alive until someone busts him out of this awful concrete box. Maybe no one's even coming to his rescue. Maybe he's got to stage one all on his own.
Eggman stands before his cell for about an hour, blocking the swarmed map, unusually quiescent. Sonic sits with his back to him. All he can see is a round shadow blocking his own.
"You know," doc begins slowly, "that blow-up yesterday got me to thinking I ought to thank you. It seems my plans have grown a little fuzzy lately, which is why I've decided it's going to be today. No time like the present, Sonic, eh? Carpe diem."
"Not going to talk to me after pulling that little stunt? Hmph. I figured as much."
Eggman turns to leave when a weak voice beckons him.
"Ninety-nine percent ain't bad," whispers a bleary-eyed Sonic, "but it's no hundred."
Eggman punches a dent in the wall on his way out.