On an even ground, it seems Harley has what it takes to disarm the Deadpool and, at the very least, mercilessly beat him up.
While Deadpool is virtually unkillable due to his healing factor, he is not invincible. In fact, he's been beaten, maimed, and dismembered countless times in the comics and movies. Deadpool's immortality only extends to his ability to regenerate from almost any injury.
Galactus could obliterate Deadpool a million times, but the Merc with a Mouth will come back every time to inflict a little more damage. There was one time in the comics when Deadpool faced Galactus head on, and somehow won.
Deadpool wouldn't be able to touch flash and flash wouldn't be able to kill deadpool. It's a never ending fight, if there was any fighting at all.
Sonic vs. the Flash: Who Would Win? At their “top” speed, no one really wins or loses. However, canon events give us hints on how fast exactly these two can run and that the Flash just had more edge and broader source material, making him evolve and grow into a better and faster version of himself.
Quicksilver, Marvel's Answer to The Flash
The other is in the Marvel Cinematic Universe, Quicksilver is played by Aaron Taylor-Johnson in Avengers: Age of Ultron (2015). Less popular, but probably because this version of Pietro didn't last long. Regardless, there aren't many things this speedster can't do.
Unlike Wolverine, whose wounds sometimes cause excruciating pain as they heal depending on the severity, Deadpool has some degree of pain insensitivity.
A mercenary for hire, he played an important role in the series Deadpool; T-Ray served to remind Wade Wilson, also known as Deadpool, what a failure he was. He is Deadpool's archenemy for many issues and almost everything that happened to Deadpool was a part of an elaborate plan orchestrated by T-Ray.
Right now, she's still a relative novice with her improved abilities. Once Wanda learns how to use them properly, there's a good chance that she will be unstoppable. Much like Hela, Scarlet Witch would simply overpower him. It wouldn't be anything close to a fair fight.
Deadpool can survive a nuclear bomb -- how hard could it be, right? The merc has been known for being indestructible, but you would have never guessed that he could survive his very atoms being blown to bits.
Cows, Clowns and Other Phobias
The fast-talking gunman seems almost fearless on the battlefield, but in reality, there's a lot that scares the Merc with the Mouth. There are two things though, that scare him above all: cows and clowns are a Deadpool weakness.
Deadpool. At some point, Weasel met and befriended Wade Wilson before putting him in a series of organized bar fights known as the "Deadpool". After Wade was diagnosed with cancer, Weasel comforted his friend by joking about his inevitable death.
Pamela Isley (aka Poison Ivy) is the deuteragonist of the DC Universe's animated Harley Quinn franchise. She is Harley Quinn's best friend, eventual girlfriend, and fellow Arkham Asylum escapee.
Harley Quinn's Biggest Fear is Poison Ivy and The Joker.
Harleen became obsessed with her subject, and after falling madly in love with the Clown Prince of Crime, she helped him escape the asylum. Her love for the Joker inspired Harleen to adopt a new identity, that of Harley Quinn, the Joker's sidekick-slash-love interest—whether he wanted one or not.
The origins of the being known as "Evil Deadpool" are tied to Ella Whitby, a British psychiatrist obsessed with the super-human mercenary Deadpool. She collected numerous parts of Deadpool's body that he had lost over the years, and kept them in her freezer.
Angel Dust (Gina Carano) is a secondary antagonist from the 2016 film Deadpool. She is portrayed by actress/MMA fighter Gina Carano. Angel Dust is a human who received superhuman strength and durability from an aumentation procedure that awakened her dormant X-genes and turned her into a mutate.
Throughout multiple timelines and multiverses, there are alternate hero versions of Deadpool as well. Wolverinepool is arguably one of the strongest and most powerful. This is not a version of Wolverine, but rather a Wade Wilson who was given adamantium in the Weapon X program, alongside the other experimentation.
Deadpool has bovinophobia, which is the fear of cows. According to him, cows "scare the *#$% outta" him, as he believes their stare to be chilling, like they're "waiting."
Due to clinical experiments, the nerve endings connected to Darkman's skin have been severed, rendering him immune to pain, but unable to feel physical sensations.
At the start of the game you can make Deadpool drink loads of beer, however Deadpool scolds the player for it and states he can't get drunk even if he wanted too.
Storm & the Brotherhood of Mutants #1 re-introduces the young mutant Loolo, first seen in X-Men Red #6, as the incredibly fast hero called Quick.
While Quicksilver is often thought of as the fastest of the Avengers, one hero fans know from the movies can actually outrace him when they need to. Many heroes possess enhanced speed, but Pietro Maximoff is generally considered Earth's fastest man (at least in Marvel Continuity).
While Eobard Thawne is the fastest villain Flash has ever faced, Black Flash is the fastest speedster of all time. This being is Death for anyone who possesses the power of the Speed Force.