Loki, the God of Mischief, has had a storied career in the Marvel Universe. For many years, he was his brother Thor's arch-nemesis. When the MCU came along, Tom Hiddleston played him, and suddenly, more often than not, he was no longer that bad. Mischievous, sure, but he wasn't evil anymore.
He still caused trouble, but when you're a God of Mischief, that's just in the job description. He isn't what one would call heroic, but he's gained a greater respect for things than he used to have. So, let's say he found a doorway into the DC Universe. What villains would fall before him? Which ones would take him down?
10 Would Lose To: Doomsday
Loki, as both a god and Asgardian, is no slouch when it comes to the physical side of things. Far from it, really. However, against Doomsday, there's just nothing he can do... at all. See, when going against Thor or anyone else stronger than him, Loki depended on his tricks to even the balance of power.
His tricks wouldn't work on Doomsday. There's nothing to trick. Doomsday is a mindless engine of destruction. It's doubtful that Loki would even be able to put up much of a fight against Doomsday. His other magics might help stay alive for a while, but he would lose.
9 Would Defeat: Sinestro
Sinestro is empowered by the yellow light of fear. Once one of the greatest Green Lanterns of all time, he's now a ruthless villain of the highest order. He's also arrogant and quick to anger. Loki would play on those two qualities and that would be Sinestro's downfall.
In the end, Sinestro is just a mortal being, and Loki is a god who excels at pushing buttons. It's what he does. He would mess with Sinestro's head so much that Sinestro wouldn't know if he was coming or going, but one thing would be for sure- he wouldn't be winning.
8 Would Lose To: Brainiac
Brainiac's cybernetic nature is what would save him from Loki. Loki would be able to survive the waves of robotic attack drones Brainiac would send for him- he was trained in combat in Asgard, after all- and this would boost Loki's confidence. However, the whole time, Brainiac would be watching and calculating.
When Loki finally faced Brainiac, Brainiac would just unload on him. Brainiac can mix it up with Superman. Superman is a lot stronger than Loki, and Brainiac would know that playing with Loki would be a mistake. He would use his brawn instead of his brains to win this one.
7 Would Defeat: Black Adam
Black Adam is vastly powerful, but he's also the type of guy that Loki can play like a fiddle. He's too emotional and Loki knows how to get the best of guys like him. Of course, Loki also would have to be careful with Black Adam- pushing him too hard to fast could result in him escalating the fight to a place Loki isn't ready for.
Physically, Loki can't match Adam, but using his magic and other gifts, he would be able to get into Adam's head and take him out.
6 Would Lose To: Mordru
A Lord Of Chaos, Mordru is one of the most powerful sorcerers in the past, present, or future. A battle between Loki and Mordru wouldn't be a physical affair, but one of two powerful magic users squaring off against one another, the kind of battle that would shake the cosmos. And Loki would fall.
See, Mordru is basically a god himself. As powerful as Asgardians are, they aren't all-powerful. Loki may know a lot of magic, but Mordru can tap into reserves of energy that Loki just couldn't. Plus, none of Loki's tricks would have much effect on Mordru.
5 Would Defeat: The Joker
Really, this wouldn't be much of a fight. There's exactly nothing the Joker could do to hurt Loki. Joker is a ruthless and cunning man, but he's still just a man. Sure, an insane man and one of the coolest villains in any superheroic universe, but a man nonetheless.
However, that wouldn't stop him from trying and it would be amusing to see Loki react to Joker's traps and tricks. None of it would avail the Clown Prince of Crime any, but he'd find the irony of a trickster god defeating him delicious.
4 Would Lose To: Solomon Grundy
Solomon Grundy is the Hulk if he was a zombie, and that's going to be Loki's undoing in this fight. Grundy is immensely strong and durable. He's also pretty much mindless, meaning Loki can't really trick him. Loki's magic may help him a little, but the problem is having time to use it.
See, Loki would probably try to trick the monster of Slaughter Swamp somehow first and when that didn't slow Grundy down at all, he'd pay. Grundy isn't some slow, hobbling zombie. He'd be on Loki quickly, hitting him. Loki won't be able to stand up to Grundy's assault.
3 Would Defeat: The Batman Who Laughs
The Batman Who Laughs specializes in taking down people who punch above his weight class. However, when it comes right down to it, Loki is too much for him. It's not just the magic. It's not just the muscle. It's not just the tricks. It's the years of experience.
The Batman Who Laughs is so sure of every single one of his plans, and Loki knows how to manipulate men like him. He's been doing it for thousands of years. Loki doesn't really have the kind of weaknesses that the Batman Who Laughs is used to exploiting when he goes up against someone out of league, either. There really isn't much the Batman Who Laughs can do to counter Loki, and that will cost him the fight.
2 Would Lose To: Darkseid
Loki is a powerful opponent, able to take on many beings much more powerful than him and defeat them. This won't be the case with Darkseid. The best way to put it is like this- Loki is a god. Darkseid is a God. A sufficiently powerful person with a sword could kill Loki. The last time Darkseid died, in Final Crisis, it took a concerted effort by the entire superheroic community, and in death, his spirit still almost destroyed the DC Multiverse.
Loki has nothing he could do to hurt Darkseid. It's doubtful that Darkseid would even consider Loki worthy of his time to face physically. He'd either throw his servants at Loki until they killed him or just hit him with the Omega Effect.
1 Would Defeat: Lex Luthor
Lex Luthor is the kind of guy who thinks he can take down a god, and this is why Loki would beat him. A guy like Lex is extremely susceptible to the type of attacks that Loki likes to use to soften up his opponents. Loki will let Lex think he's winning because that's when Lex makes the most mistakes.
Once that happens, it's only a matter of time before Loki takes Lex out. He just has so many things he can use against a man like Lex to beat him, and while Lex could beat Loki if he could somehow resist his magic, Lex wouldn't be able to overcome Loki's power.