Pyrrhic victories make for great stories, something the creators who work at Marvel Comics have learned over the years. Named after Pyrrhus of Epirus and his disastrous victory over the Romans, the phrase is used in storytelling to represent a costly victory that's barely worth the price paid. The Marvel Universe is full of such victories that have hurt the heroes and teams in the long run.
Marvel's heroes have battled terrifying foes like Onslaught, Thanos, Doctor Doom, and even engaged in civil wars with each other and some of these victories weren't worth the effort. These battles often had unintended consequences so costly that the victory was basically a loss.
10 The Battle Against Onslaught Cost The Avengers And Fantastic Four
Onslaught's attack on New York City was devastating. The psychic entity used reprogrammed Sentinels to hold the city hostage while draining massive amounts of power from X-Man and Franklin Richards. The X-Men, Avengers, and Fantastic Four teamed up. To defeat Onslaught, the X-Men attacked the bodies of the human heroes that were containing Onslaught's energy.
Onslaught lost, but only briefly. The loss of the Avengers and Fantastic Four left a vacuum that the Thunderbolts filled, with disastrous results. The X-Men were blamed for the disaster, which made it easy for the government to unleash Bastion and Operation Zero Tolerance against them.
9 The Avengers Beat The Builders But The Multiverse Was Still Doomed
Infinity, by Jonathan Hickman, Jim Chueng, Mark Morales, John Livesay, David Meikis, Justin Ponsor, Chris Eliopoulos, and Joe Caramanga, presented two battles. The Avengers fought the Builders as they tried to destroy all life in the universe, while Thanos and the Black Order invaded Earth to kill Thanos's Inhuman son, Thane. The Avengers and the New Avengers both triumphed, but it was ultimately meaningless.
The Builders were destroyed, but it did nothing to stop the Incursions they'd created. Even the battle against Thanos was ultimately meaningless, as he'd eventually destroy Thane down the road. On top of that, Black Bolt releasing the Terrigen Mists led directly to the war between the X-Men and Inhumans, which destroyed Inhuman society.
8 Inhumans Vs X-Men Didn't Do Any Favors For Either Side
Speaking of the war between the X-Men and Inhumans, Inhumans Vs. X-Men, by writer Charles Soule and Jeff Lemire and artists Leinil Yu, Kenneth Rocafort, and Javi Garron, was as Pyrrhic as they come. The battle started with the loss of Cyclops, Multiple Man, and more, but the two groups didn't come to blows until the Terrigen Mists reached their saturation point in the atmosphere.
The endgame saw the X-Men and Inhumans team up to stop Emma Frost from using Sentinels to destroy the Inhumans. Medusa destroyed the Terrigen Cloud, which doomed Inhuman society, and the X-Men lost access to Emma's fortune.
7 The Destruction Of Mother Mold In House Of X Was A Stop Gap Measure
House Of X/Powers Of X changed the X-Men mythos forever. The establishment of Krakoa caused the Orchis Initiative to take effect. Using information gained from the past lives of Moira MacTaggert, a small team of X-Men attacked the Forge, Orchis's space station in solar orbit, to destroy the Mother Mold and prevent Nimrod's construction.
The X-Men succeeded, but every team member died. Krakoan resurrection brought them back, but the whole mission was futile. It told Orchis that mutants had conquered death and Nimrod was built not long after anyway.
6 Restoring Reality In House Of M Had Dire Consequences For Mutantkind
House Of M, by Brian Michael Bendis, Olivier Coipel, Tim Townsend, Frank D'Armata, and Chris Eliopoulos, saw Scarlet Witch transform reality. She created a world where mutants were ascendant and many of her friends lived their best possible lives. Wolverine still remembered the old world and met Layla Miller, a mutant who also remembered and could unlock the memories of others. They returned other heroes' memories and set out to fix the world.
This move had huge consequences. Scarlet Witch got involved when her brother, Quicksilver, was endangered. She reverted the world to its prior state, but also removed the vast majority of the mutants' powers, killing thousands.
5 The Battle Against Magneto In Fatal Attractions Was Costly
In the Fatal Attractions story arc, Magneto and the Acolytes tempt X-Men to their cause before attacking humanity. Running through every X-Men book in 1993, Professor Xavier led a team of X-Men to Magneto's base, Avalon, for a final battle. The X-Men won, but Magneto ripped out Wolverine's adamantium and Xavier retaliated by wiping Magneto's mind.
Wolverine nearly died and left the X-Men, hurting the team. Beyond that, the erasure of Magneto's mind led to Onslaught's creation, as the evil inside the Master of Magnetism merged with Xavier. This composite being almost destroyed the human race in subsequent stories.
4 The Phoenix's Death Devastated The X-Men
"The Dark Phoenix Saga" is an X-Men classic. Written by Chris Claremont with art by John Byrne, Bob Sharen and Terry Austin, and lettering by Tom Orzechowski, Jean Grey's fall to darkness ended with a trial by combat. Brought before the Shi'Ar Empress Lilandra for Phoenix's crimes, the X-Men were pitted against the Shi'Ar Imperial Guard. If the Guard won, Jean was to be executed.
The Imperial Guard trounced the X-Men. To save her friends and the universe, Jean destroyed herself. The X-Men won, but they also lost what they were fighting for. Jean's death changed the team's outlook on reality until the truth was revealed and the real Jean returned.
3 Nighthawk's Faction Beat The Squadron Supreme But The Cost Was High
Squadron Supreme is a must-read for every Marvel fan. Written by Mark Gruenwald with art by Bob Hall, Paul Ryan, and John Buscema, the titular team decided to institute a benevolent worldwide dictatorship. It started out well, but the heroes soon resorted to totalitarian tactics. A schism formed within the team and the two sides eventually clashed.
In the end, Nighthawk's rebels were able to beat Hyperion's forces, but there were deaths on both sides, including Nighthawk. Though this "civil war" concluded, the Squadron disbanded, and their world would never be the same again.
2 Civil War Broke The Superhero Community For Years
Civil War is the most important Marvel story of the 2000s. Created by Mark Millar, Steve McNiven, Dexter Vines, Morry Hollowell, and Chris Eliopoulos, the battle between Captain America's rebels and Iron Man's pro-Registration forces became fiercely personal. Iron Man's eventual victory didn't fix anything. In fact, it made things a lot worse.
Cap's surrender made it easier for Red Skull to assassinate him. Cap's anti-Registration team kept defying Iron Man, weakening the integrity of the entire superhero community. Beyond Cap's death, heroes like Spider-Man, who revealed his identity to the world, lived in fear for months. Iron Man's focus on defeating his former friends blinded him to other threats, like the Skrulls.
1 Secret Invasion Led To The Dark Reign
The Secret Invasion storyline changed the face of the Marvel universe. The Skrulls quietly replaced heroes and members of S.H.I.E.L.D., while the anti- and pro-Registration Avengers were lured into a trap in the Savage Land. The heroic groups joined forces, along with the Thunderbolts and the rest of the Superhero Initiative, against the invaders in a climactic battle.
Wolverine was on top of the Skrull Queen Veranke. She managed to get some distance between them, though, which allowed Norman Osborn to get the kill shot. This led to Osborn taking over the Superhero Initiative, driving all heroes underground and allowing villains to take power. The "Dark Reign" that followed almost destroyed the world.