Black Mage returning as Hellking and banishing Lich to Hell.
Red Mage slaying Ur from the inside right before the apocalypse started.
Dragoon killing Muffin as she had Thief in her hand.
And finally...White Mage and 3 other white mages killing Chaos.
In All Manner Of Bad the hideout was attacked while half the group was away retrieving family and loved ones. One of those characters made an end of the world plan with his wife that included zombies. Upon their return he and his wife open fire on the huge horde of zombies attacking their hideout (and former workplace). Partially subverted in the last panel as their self-proclaimed bad assitude is wittily rebutted.
In Blue Yonder, once Jared has sent back some news, the heroes at Clairmont Apartments realize what danger he's in.
Invoked in Buttlord GT, where Buttlord gets to the battle on time, but refuses to interfere until his allies are half-dead.
In Collar 6, just when it looked like Sixx was lost to Butterfly and Trina, Ginger and Laura break into subspace, which should have been impossible for the latter. Ginger takes out Trina, and Laura gives Sixx a Cooldown Hug, giving her the strength to withstand Butterfly's assault.
When Brayden Katanning gets cornered by two hungry leopards on a delivery run, his employer, Fortenflack Schlag, actually risks missing his daughter's birth to rescue him. Not that Forty is entirely opposed to "wild meat", but letting one of his employees get eaten would be a grave insult to him—and, by extension, his entire clan and Boss Alpha Blutenstein. Fittingly, the strip where the leopards get the spots beaten out of them is titled "Respect Lesson".
A small one in Dreamkeepers Prelude: To condense what leads to it, a drunken, enraged Grunn (the abusive owner of the orphange), after losing most if not ALL of his fishing boats, finally gets so angry that he just snaps and starts throwing the orphans several meters out to sea so that they'd be forced to bring them back. (Admittedly, he had few choices left to get his boats back, his only viable means of making money was selling the catch brought in by those boats, and he had just been repeatedly hit in the face with an oar...) Vi, who somehow avoided Grunn, swims all by herself out to the other orphans (Who are just hanging out on an overturned boat, apparently forgetting that Grunn is waiting for them on land...), putting herself in danger. Why would she do something so reckless? To tell the others that the tide is going out and that the boat is riding lower. If she had shown up much later, the roughly six or seven guys just chillin' out would have been stranded at sea and, eventually, drowned.
Dregs: Subverted for laughs with Mags arriving in the nick of time to help foil the Baron — and then almost immediately legging it when she realises the bomb is armed. Bandy awards her a "you tried" medal for this.
Tedd in El Goonish Shive pulls a non-violent one. Not to mention a more violent one at the end of the Sister II arc from Nanase.
In the Korean webcomic Fluttering Feelings Kim No-Rae saves her new friend and neighbor Baek Seol-A from an ex-boyfriend who tried to strangle Seol-A to death for having the audacity to break up with him after he cheated on her. Hopefully No-Rae's bat hit some sense into him.
Gaia: Ars becomes one when he saves two girls from an assassin during the Red Hall attack.
Guilded Age: When they find Penk and Magda trying to stop the otherworldly beast from reaching innocents, the Peacemakers decide they can't stand by and watch, so Frigg and Rachel ride WAV's Cool Bike down the cliff and crash into it.
Antimony from Gunnerkrigg Court finds herself on the receiving end of this three separate times (some less successful than others).
Lore Olympus: Hecate arrives just in time to rescue Hades from further abuse from Minthe, suspending her until further notice. Eros also gets a moment to shine when he arrives to save Persephone from Apollo when she confronts and tries to explain how much she despises Apollo.
Pulled twice by different characters in this strip, plus lampshaded:
Bozzok: Damn it!!! How do the good guys keep DOING that???? Belkar: Trade secret.
Belkar has one moment when he is cured from the curse that left him half-comatose for several weeks of comics.
Belkar: Back me up and I'll cut a path through these guys. Wait, did I say "path"? I mean a five-lane blacktop highway with a two-lane service road - and I'm packin' a fist full of tokens and a radar detector.
Big Damn Heroism seems to be an inherent ability for the extremely Genre Savvy "Dashing Swordsman" class, even granting Elan a sixth sense for where he needs to appear in the nick of time. And much later, Julio himself gets in on the act...
Pacificators has several of this (the standouts are Larima Torbern's introduction, and the stunts for the entire platoon in the latest chapters).
In the "Armadeaddon" story-arc in Penny Arcade, it looks like Gabe and Tycho are about to be overrun by the zombie horde when they are saved by Fruit Fucker! Fruit Fucker: Make Fruit Your Bitch. And stopping a zombie apocalypse is part of its programming—Code Omega.
Fruit Fucker has joined the party!
Just as Susan and Anna from Sire are about to be preyed upon by a bunch of London thugs, Emile, the Javert child arrives and administers justice.
Skyvein: Taisce saves a human in Chapter One in a glorious, waterbending moment; later in that same chapter, a couple of mysterious fey save them in a similar way.
In Chapter 3, when Undine returns to the scene of the monster attack that killed her teammates, the same shadowy presence appears again to taunt Undine before summoning another monster to finish her off. But just when things aren't looking good for her, a heart-shaped blast blows a hole clean through the monster, and magical girl Heartful Punch makes her dynamic introduction.
After narrowly managing to take down a powerful monster during Chapter 8, Undine and Heartful Punch take a moment to catch their breath... only for the monster's remains to split into several smaller monsters and continue their attack. Luckily, Team Outrageous arrive on the scene with a particularly showy introduction and proceed to help them clean up.
Sluggy Freelance: There's one in the Vampires storyline, when Riff, Bun-bun, Aylee and Kiki head to save Torg and Zoë from vampires. Delays caused by Bun-bun and the others cause them to arrive in the nick of time too, though they had several days to start with. Played only partly straight in the end, as Torg and Zoë end up killing the most important vampires themselves, albeit only enabled to do so by the help.
First happened when Hoh attempted to murder Rachel. While ranting about dealing out justice in God's stead to her, Quant, the test administrator, appears.
"A mere Regular acting on the behalf of God? What impudence! The god of this testing area is ME!"
When Anaak and Endorsi get beaten to near-death by Ren and things are really getting ugly, Yuri shows up and saves the day with her finger flicks of doom.
Just when Rapdevil is about to kill Prince, Kang Horyang appears and beats the shit out of the Da-an Guard and RD.
Mia successfully pulled this off despite her size, to the amazement and fist-pumping of many.
In fact, she pulls this off TWICE, once with the building of Tom and a second time with The Punching Fist of Fury.
Unsounded: When Starfish tries to renege on his deal with Quigley, manages to grab Matty promising that at best he can take the just escaped child slave Jivi's place once his father is dead, and is gleefully watching as his new wright drowns Quigley, Jivi breaks through the door of the warehouse on Uaid and rescues both Quigleys.
Vampire Cheerleaders: Near the end of the comic's final volume, B-Squad pulls a last minute save by rescuing Leonard and Suki just as they'd been about to be sucked into space. Then they clear a path so Steph and the few remaining survivors could escape Mothworld's destruction. The page itself is even titled: "B-Squadron to the Rescue".
Several of these in The Water Phoenix King have been subverted or ambiguous (everyone chasing around in the tunnels in Chapter 1, the anticlimactic fight in the clearing in Chapter 2) but when Gilgam and the Commander finally arrive at the inn just in time to give the magic-users cover enough to repair their defenses at the conclusion of "Pride of the North" it's classic, and Book 4 takes it up to 11 when Anthem and Vish are the only ones left to go try to rescue all the real warriors from the Temple...CMOA, bringing a lot of themes full-circle there.
When Gray is ganged up on by five students- a number even he is hesitant to face- he's saved from a beatdown by Gerard, Ben, and Alex joining the fun.
Eugene, of all people, gets his moment of heroism after the fight with Jimmy Bae. When one of his goons tries to sneak up on Gray with a wooden board, Eugene leaps out of hiding and tackles him before he can hurt Gray.
In the fight against Hyeongshin, Alex is ganged up on by six students. He's saved from a thorough beating by Teddy, who had noticed the gang following him beforehand. He fights back the aggressors and then they both make a run for it.
As revealed in a flashback, Alex was about to lose consciousness after being beaten by Jimmy when Ben arrived at the last moment, fighting both Jimmy and Donald to protect Alex from further harm.
Lewie in Yet Another Fantasy Gamer Comic had to leave the Mountain on rather bad terms with everyone. He returned when they kissed their butts goodbye, apparently from under their current problem, with a blazing mushroom cloud and the comment "Hah! Gotcha!". Just a reminder: Lewie can be a badly messed-up goofball, but he's also a very old, overpowered and Nigh-Invulnerable spellhurler.
Yo-Jin-Bo has its own moment of the heroes saving the other half of the heroes. Sayori trips and falls as she and Muneshige are running to first escape the castle. The ninjas have her surrounded and are about to kill her. Enter five wise-cracking heroes. Those poor ninjas never regain their competence.
In Zokusho Comics just as a goblin sorcerer is about blow up a ten year old, Jin comes out of nowhere and twists the goblin's head around 180 degrees.
while half the group was away retrieving family and loved ones. One of those characters made an end of the world plan