Deadpool has been slicing and dicing his way through Marvel Comics since 1991, and little has changed about his character. He has as many enemies as he does allies, which means he has had to endure many incredibly brutal injuries. Though he has a quick healing factor, those wounds had to have hurt quite a bit.
From simple beheadings and stabbings to being torn in half multiple times and worse, reader discretion advised is an understatement. He has been through a lot in his thirty-plus years of existence, but some maulings are much worse than others.
Turned Into A Cape
In one of Deadpool's more recent conflicts, he was attacked by a new Marvel character called Good Night, similar to DC's Dark Knight, in Deadpool #11. As violent as Batman is, however, Good Night is at least ten times worse. After taking several of Deadpool's merc jobs, they eventually clash and Deadpool is defeated, but his pain does not stop there. Good Night hangs him on a wall and methodically removes all of his bones as a way of torturing him.
Taking things a step further, Good Night then uses Deadpool's boneless body as a cape, a very macabre and twisted action. So, why was Good Night so intent on going after Deadpool? Apparently, the merc with a mouth killed his parents in a similar fashion to how Batman's were killed. Nothing is more brutal than a revenge quest.
Anvil Dropped On His Head
An injury that could have come out of an R-rated Looney Tunes, Deadpool Team-Up #885 has the mercenary meeting someone in a dark alley. What makes this even more suspicious is that this person contacted him online. The anvil does not fall on him instantly, though. In typical Deadpool fashion, he becomes distracted by the simplest thing: a four-leaf clover, while also failing to comprehend the meaning behind a giant X painted on the sidewalk.
Technically, the anvil swung into his face rather than dropped on him, but regardless, it hit with immense force. This is random, gruesome carnage at its finest. Either he did see this kind of thing coming and did not care, or he was completely surprised by this turn of events. It is hard to tell what Deadpool is thinking at any point in time.
Chewed Off His Arm
No matter the circumstances, an injury is an injury. Deadpool #900 finds Wade kidnapped by some interesting Deadpool comic book villains, grotesque aliens, who had the intent of experimenting on him. Since he was already the product of an experiment, he was in no hurry to barely survive another one.
However, he cannot fight back in his usual way, as his weapons were taken from him and he had been stripped naked. As a result, he resorts to drastic measures: chewing off one of his arms. Considering it did not appear to take him long to detach his arm, Deadpool must have known just where to bite to get it off quickly before the aliens could stop him. Desperate times call for desperate measures, apparently.
Crushed By Thanos
Someone thought it would be a brilliant idea to have the merc with a mouth face off against the cosmic juggernaut Thanos, and thus, the Deadpool vs. Thanos miniseries was born. Why were they fighting? Over a love interest, of course. Deadpool has had many strange romances in his life, but the woman he and Thanos are fighting over is none other than Death. Yes, Death is a woman in the Marvel comics universe.
While Deadpool is after Death for more physical reasons, Thanos believes he is in love with her, so much so that he is borderline obsessed and will do anything in her name. This leads to Thanos brutally beating Deadpool into a bloody pulp, and this was without the Infinity Gauntlet.
Sue Storm Explodes His Head
Deadpool's first mass killing spree in Deadpool Kills the Marvel Universe has him facing off against Sue Storm, A.K.A. the Invisible Woman. Though she is invisible when he gets to her, he is still able to find her, as there is blood splatter on her suit. Considering he just killed her brother, it is safe to say that the blood is his.
Deadpool is about to attack her when she puts a forcefield in his brain and expands it, popping his head like a balloon. The pressure build-up alone had to have seriously hurt. Of course, he recovered and was able to kill Sue in the end, but putting his head back together had to be a miserable experience.
The Hulk Tears Him Apart
In another event in Deadpool Kills the Marvel Universe, Deadpool comes across the Hulk in a desert cave, and they proceed to fight each other. Of course, Deadpool is outmatched, and the Hulk brutally tears him limb from limb, even tearing off his head.
In a rare moment of intelligence, Deadpool lets the Hulk think he died and waits for the green giant to wander off. It must have been difficult to think of a good plan when in pieces like that. After he puts himself back together, he finds the Hulk again, this time as Bruce Banner, and waits for him to wake up before cutting off his head in some twisted sense of irony.
Stabbed With A Chainsaw Sword
What makes this brutal wound kind of funny is that Deadpool is being stabbed by Deadpool; well, an alternate version of him anyway. During the Deadpool Kills saga, the merc with the mouth hears a third voice in his head telling him to kill everyone in the Marvel universe as well as various other fictional characters. In response to this, alternate versions of himself start showing up and trying to stop his bloody crusade.
The main Deadpool then gets run through by a chainsaw sword, causing twice the damage only one of them would. Not only does he get stabbed by the sword, but he also has to deal with the spinning chainsaw blades. The only person who knows Deadpool better than himself is...well, himself. And his alternative self had to know that being stabbed by a chainsaw sword hurts.
Carnage Tears Him Apart
Carnage is a symbiote, which means he can change his malleable body into whatever he wants. This includes morphing into a giant monster and turning his hands into sharp weapons. Needless to say, Carnage is often a danger to the world in Marvel comics, and he is a force to be reckoned with. This does not stop Deadpool from going after him, though.
They clash in Deadpool vs. Carnage, and the use of red has never been so prevalent. They both go at each other in a no-holds-barred brutal and bloody battle that results in Carnage slicing Deadpool to pieces. Neither of them can die easily, so it is a fight that could go on for ages unless one of them yields.
Gored By An Elephant
In quite possibly the weirdest set of circumstances Deadpool has ever been through, how he comes to be hanging from an elephant tusk is quite the story. Deadpool #2 sees a man using magic to bring back long-dead presidents in a misguided attempt to save the United States. Of course, this backfires on him, and the undead presidents decide that the only way to save the United States is to destroy it.
Deadpool thinks it is a great idea to spend the day fighting presidents, though he is unprepared for how ready they are for someone like him. Thus, he is brutally gored from behind by an elephant. Deadpool, to his credit, had enough energy to muster one smart remark through what were surely gratuitous amounts of pain.
Eaten By Zombies
This is a situation not even Deadpool could fight his way out of. In Night of the Living Deadpool, he wakes from a coma to discover that the world has been overrun by zombies, and he is the only living person around. He does try to survive for a while but ultimately succumbs to the overwhelming horde.
Considering there were so many zombies, there is a chance he did not suffer for too long, at least. An interesting phenomenon happened once the zombies got to Deadpool's brain; his consciousness overrode the zombie virus and took control of them, and they began to spread his control to other zombies. He then became a hive mind and achieved omnipotence through the undead. Even when Deadpool does not have a body, he still finds a way to keep going.