It might’ve been Halloween, but the only thing scary was the action between a Colombian cazadores in search of a title, and a bantamweight monster, who entered the ring in a gorilla suit, chained and led by a hot blonde, and left without his belt, a dozen whirlwind rounds later.

Yielding up this year’s gem, Treasure Island, in the first-ever fight card held there, saw one king toppled, one King return and another former king turn color commentator.

The ballroom at T.I. packed in the bodies for an intimate setting on the Showtime-televised, Don King and Gary Shaw-promoted “Halloween Thrilla.” Not only was it the first Vegas promotion in five years for former Sin City king Don King, but it marked his reunion with former heavyweight champion Mike Tyson, who was added to Showtime’s crew of commentators.

In the main event of the eight-bout card, IBF Bantamweight Champion Joseph “King Kong” Agbeko, of Ghana, who rose to star level with his defeat of Vic Darchinyan in his last outing, was toppled from his throne by hungry Colombian, No. 1 Contender Yonnhy Perez.

With the opening bell, Agbeko launched himself at his challenger, who willingly traded shots. Once the war commenced, there was no let-up. Back and forth, up and down, in and out, the two slugged their way through crafty defenses, blasted away with relentless aggression and absorbed one another’s shots.

The continuous motion had to be a nightmare for any judge; it was further hindered by a monstrous glare from the low-hanging lights.

Up to the tenth round, the fight was a cyclonic rollercoaster ride, each round a near duplicate of the one before, with Perez proving himself the slicker fighter and Agbeko, the more aggressive. In the earlier rounds, the harder-hitting Agbeko worked his way in, and through, the guard of the taller Perez, but the Colombian proved the better counterpuncher and sharper jabber.

Neither fighter blemished the battle with a single inclination to clinch and, despite a few head clashes, while the two feverishly striking at close quarters, neither one voiced a complaint.

Until the telling tenth round, that is.

After a headbutt that had Agbeko turning his back to Perez to nurse the damage, the challenger took advantage of the situation by landing murderous shots to his wounded opponent. Two up top and one big left to the body folded the champion to the canvas. While Referee Robert Byrd counted, Agbeko rose to complain.

For many ringsiders, who had the fight at flip-a-coin status, the knockdown was looking like the decision-breaker.

When the fight resumed, Agbeko showed little damage, redoubling his efforts to win back the lost round. Working his way within range, he continued to slugging away but Perez, the better boxer, landed the cleaner, albeit less quantitative punches.

No one really had a clue who won. Both corners raised their fighters up on shoulders for victory posturing, but the expressions on faces in and around the ring said, “Your guess is as good as mine.”

The judges, however, had seen a definitive fight, for the scorecards were unanimous: 117-110 twice (Judges Glenn Trowbridge and Barry Druxman) and 116-111 (Jerry Roth), all for Perez.

Fightnews had it 114-113, for Perez, reserving the right to alter the numbers upon a replay without the glare of the lights.

“I knew I was winning the rounds and I deserved to get the victory,” said Perez, who sported twin gashes on his brow from the fight.

“I felt I was more consistent, more active and I pressed the fight throughout … I trained to throw a lot of punches. I know Agbeko likes to throw a lot of punches, so I knew I had to be better conditioned. All the hard work and preparation paid off. This is a dream come true.”

With the win, Perez keeps his record spotless, rising to 20-0, with 14 short ones.

Agbeko tastes defeat for the first time since 2004, falling to 27-2, 22 KOs.

“He head butted me in round ten,” the former champ complained after the fight. “I don’t think that was fair. The reply clearly shows what happened. I was fighting well to that point. I thought I was winning the fight. Perez seemed energized after being awarded the knockdown and I was never the same after his head hit mine. We will never know what would have happened had there not been a head butt.”

Perez, on the other hand, attributed the knockdown to a lack of stamina.

“I don’t think he was in good shape,” said Perez. “I think he went down to catch his breath.”