Archie Comics' Sonic the Hedgehog turned the Great War and its leadup into this. Ixis Naugus wanted the throne, Warlord Kodos wanted war and Julian Kintobor wanted the world. It took awhile and some double crossing from each other, but all three got what they wanted.
Pre-reboot, The Blackblood Alliance had one of these. The saberteeth are trying to conquer the wolves of Inaria, who seek help from the Blackblood wolves, who Blade's faction are plotting against. But only some Blackbloods want to help Inaria, so the Blackblood group quickly splits in two. Also, there is a secret group of malcontents within Inaria's pack who want to usurp the current alpha(s), so they orchestrated the Blackblood wolves' exile years before. Now, the Blackblood wolves actually know about this faction and what it did to them, but the Inarian pack refuses to believe them, partly because the malcontents are led by one of the alphas' daughters. All this is established in one issue.
A Calvin and Hobbes Sunday strip features a game of football between the namesake characters, for the duration of which they reveal gambit after gambit ad ridiculum, to great comedic effect; Calvin is a double-agent for the opposing team posing as a member of Hobbes's team, however Hobbes knew the whole time and secretly switched the location of their goals, etcetera etcetera. Naturally, it ended up turning into Calvinball.
He plays with it in Quantum and Woody, where Quantum often suspects these, but is usually wrong.
Once in a while, Diabolik has a story where the protagonist has a fight with Eva and decides to make an heist alone and Eva decides to one-up him by making that heist before him, resulting in their plans interfering with each other. If the victim is a criminal, there's a good chance that Ginko or another cop is investigating him, further complicating things (and in at least one occasion causing Eva, who had already stole the loot, to frame Diabolik as The Mole who informed the police. The actual mole was Eva's roommate).
In Fall of Cthulhu, each of the elder gods has a gambit running and mankind will be lucky to survive, since we barely qualify as pawns.
The 2011 Journey into Mystery series: Loki goes up against HIMSELF. Things get very complicated and nobody wins.
In Judge Dredd, Mega City One ended up in one of these following the events of Chaos Day and Luthor's Insurrection, with various machinations and power struggles against numerous individual and factions, both internal and external, such as their own Black-Ops Division, Texas City, Total War, the Sons of Booth, rogue Citi-Def units, the Dragon and individuals such as Senior Brit-Cit Judge Gulliver Mayhew, Gideon Dallas, Carol Smart and the Red Prince amongst others.
The French comic Largo Winch has an album devoted to this. First we have a young woman named Saidee join a friend of Largo's and get invited to her art exhibition. Meanwhile an old flame of Largo's secretary shows up, while his daughter says she's Largo's Number Two's new Sexy Secretary. Then it turns out Saidee is part of an Islamist terror cell, sent to make friends with the artist so as to get close to Largo and kill him and his Number Two. Then it turns out the imam running the cell is Only in It for the Money (being both blackmailed by, and promised 40 million dollars from, the CIA), with no intention of sacrificing himself for the cause (but the rest are apparently true believers). Then it turns out Saidee is actually working for the same CIA agent, who're holding her brother hostage in Guantanamo. The father and daughter team mentioned above were actually industrial spies. And then it's revealed the CIA agent is actually working for another industrialist (the actual CIA is not involved), with the money the imam's supposed to collect actually intended for him. The album's name? Chassé-croisé, which is close enough to Gambit Pileup.
A storyline in Nodwick, which started with the heroes' attempt to stop an Orc Invasion of two kingdoms, turned into one of these for comedic effect. Especially when it was revealed that every person in the palace was attempting to control the kingdom one way or another. Story starts here, revelation of gambits starts here, page most relevant to this trope is this one.
Nodwick: Piffany, we'll have even more conspirators to add to the chart. Piffany: Oh, I gave up when Jules arrived. I'm just going to draw some duckies and bunnies for a while.
And that exchange came after our heroes learned that everyone in the krutzing KINGDOM had some sort of plan in the works or in motion.
Yeagar: If you're serious about it, getcher butts up here and take a number!
In Red Robin Tim takes the assassin Scarab out of prison in order to interrogate her on the source of her advanced tech since the authorities haven't even been able to uncover her name; in turn she agrees to go with him in order to lead him to a trap so that an organization she belongs to can enter an assassination tournament to find the best assassin of the age in which he's been set as a target. The attack gives him an excuse to look into the long running tournament and her a chance to escape even though the other members are caught. Then he's abducted by the Daughters of Acheron when trying to interfere in their entry into the tournament as they want to use him in their own long planned ceremony while simultaneously winning the tournament, though they're possibly being manipulated by Ra's Al-Ghul to his own ends, and the tournament itself was set up by a mysterious ancient figure who wants to kill the most dangerous assassin of each generation rather than reward them and who is also looking for an heir for some of the duties they've created for themselves. Then Flashpoint prevented everything from playing out.
In Supergirl's Gates/Igle run, Alura orders her daughter Kara to capture Reactron and bring him back to New Krypton. When Supergirl drags him along to the planet, a mob attempts to lynch him and Alura takes advantage of the ensuing chaos to fake his death, throw him into a cell and torture him for information... which was a bad idea because Lex Luthor and Sam Lane had turned Reactron into a living bomb ready to go off and take the whole planet with him.
In an issue of What's New? with Phil and Dixie dedicated to spy-based RPGs, two battling Cold War-era agents intersperse their gunfire with insults ("Imperialist dog!" "Commie scum!"). Each spy taunts the other, revealing that he's found the well-hidden proof that the other is The Mole. Both spies cry "What?! Then my cover's blown!" in unison, then go back to fighting each other, slinging the same insults, but with their political loyalties reversed.
The X-Men crossover Messiah Complex has everyone with the same goal, the first mutant born since M-Day who just happens to be a baby. So we have Cyclops' main group going after the Marauders (who are also looking for the baby that the X-Men think they have), getting X-Factor to both infiltrate the Purifiers and explore two future timelines for information, the New X-Men going off on their own to attack the Purifiers, Lady Deathstrike and her men helping the Purifiers as a favor, Predator X hunting after the baby's powerful mutant genes to eat it, Professor X trying to get the New X-Men on his side (and failing), Cable with the baby trying to avoid everyone else and go into the future to protect and raise the baby, Mystique using the Marauders to get the baby and save Rogue's life with the help ofGambit AND FINALLY, Bishop trying to kill the baby under everyone's noses to avoid his horrid future and using a techno-organic virus to turn the Sentinel pilots around the mansion into killing machines to buy time. Did you get all that?