The Heroes continued on down into the cavern, Sam carrying Alice on his back, until they came across a black door set in the face of the rock. Sam nonchalantly kicked it open and stepped through into a huge room furnished like a concert hall with a stage at the far end. Standing on the stage was the Sam in the reasonably dark outfit, holding in his hands a microphone stand.
"Ladies and gentlemen!" he yelled into the mic.
"Shut up, we can hear you, there's no background noise or anything!" Sam yelled back. His dark side ignored him.
"Welcome to the Anti-Sam stage! Now, I know what you're all thinking;" The Anti-Sam held the mic stand like a sword and pointed it at the group. "Surely, since this guy is Sam's darkness, he should be the final boss? Well, to that I reply: you're thinking too small. Young Abstract: how strong would you say he was compared to the other Sam?"
"Uh... maybe a little bit weaker?" Sam hazarded.
"Right. And, since I'm basically you, wouldn't you imagine that I'd be pretty much the exact same level of strength?" The Anti-Sam smiled; not a wide grin, like those Sam was known for, but more of a subtle, easy-to-miss upturn of the corners of the mouth. "Now, tell me; if we're going up in an ascending order of strength, where would it make logical sense to plonk me? Below the stronger ones, yes," he carried on without pausing. "So, tell me now; if you do somehow manage to get past me (which I don't intend to happen) then how are you going to cope with three or four, I've lost count, even stronger adversaries?" None of the Heroes said anything. "Exactly. Now, come at me."
Sam complied, drawing a katana from his bag and rushing towards his foe. Moving like lightning, the Anti-Sam dispelled his mic stand in a flash of black flames, then summoned an almost-identical-to-Sam's-but-with-a-slightly-darker-palette katana of his own. Dropping into a stance that perfectly mirrored that of the other Sam, the Anti-Sam met his blows exactly, striking each one away with a perfectly copied blow of his own.
"You remember that bit in Ocarina of Time, Sam?" the Anti-Sam asked, trading hits with his opponent. "The Dark Link fight, in the water temple? You remember how bloody hard that was?" Glados ran over to the pair, carrying her turret on her shoulder, and let off a slew of missiles; leaping to a distance away from Sam, the Anti-Sam dispelled his katana and summoned a turret of his own, cancelling out all the missiles with missiles of his own by firing them so that they met in mid-air and exploded a safe distance away from him. "He'd keep matching your moves, and so neither one of you would ever be able to get a hit in..."
"He couldn't block the Megaton Hammer, asshole!" Frank yelled, charging at the Anti-Sam and attempting to grab him. Anti caught Frank's hands in his own and Frank struggled against him, but he was being matched by a force perfectly equal to his own and could make no ground.
"What, seriously? Dammit! I spent, like, two hours on that fight! You bastard!" Taking Frank by surprise, the Anti-Sam suddenly dispelled his ability, slipping his fingers out of Frank's hands and crouching forward before headbutting Frank in the chin. Skipping away to the side, the Anti-Sam loosened up and turned to face all of his foes. "Well, as it happens, I'm not weak against the Megaton Hammer. In fact, I'm pretty invincible. Now, the question is; how invincible?" He did a quick head-count. "Seven heroes worth of invincible? I'm afraid, boys and girls, I don't doubt it." Summoning his weapon anew, the Anti-Sam charged back into the fray.
