Silver Surfer It's self-explanatory

Oh wait. Arceus. He's not reality warping, but stuff will burn away. And, if he becomes a ghost type, your non-element based (normal) attacks will have no effect

Itachi's tsukiyomi

Magnus from Skyrim, he created the entire mortal plane and some of the artifacts left behind by him are powerful enough to destroy the world and more. When he entered the mortal plane, he was so powerful upon entry, it created stars. Since he is an aedra he's also pretty strong and since he created the plane that flash is bound to, he could probably find some ways around flash's power without reality warping

Speed Demon because he's the flash but mixed with ghost rider.

Fn-2199[spoiler]also known as tr-8r[/spoiler]

What does reality warping mean?

Mr. Rogers in a blood stained sweater

Okay see here's the thing about Saitama though. He would easily win. He doesn't need to warp reality. His reflexes, speed, and brute strength would allow him to take out the Flash without the need for any superpowers. OP is beyond lettuce

This'll be a long one: Most common reasons that the Flash loses - Overconfidence. He very rarely goes into a fight taking it seriously, and even more rarely just rockets in at high (for him) speed and feeds the target a knuckle sandwich. Terrible impulse control. Flash's overconfidence and sense of humor lead to him doing a wide variety of dumb things, many of which amount to shooting himself in the foot. Smart villains. Most of Flash's Rogues Gallery know that he doesn't take them seriously, and take advantage of it at every opportunity. Major Achilles heels - Traction. If he hasn't got any then he's screwed, at least briefly. Flying. He can't, and if an opponent can then he's limited to throwing things at them or making ramp jumps. Atmosphere. He has to breathe, and can't move nearly as fast if he's in a substance denser than air. (Water, for example.) Gravity. Increased or decreased gravitational force can cripple his ability to function. More than about 2Gs is enough to make even very strong people struggle, at 3 he's probably face down struggling to breathe. At .3 he's doing his best John Carter of Mars imitation. Psionic or magical attack. Anything that doesn't have to physically HIT him to be effective is incredibly dangerous to the Flash because he has no means to counter it. Direct mind-to-mind battle against a weak telepath MIGHT go his way just because he can think faster than normal, but that's it. People immune to kinetic energy. If being punched, hit or stabbed doesn't hurt you, he really doesn't have very many options left. People (off the top of my head) who can take on Flash and win - Any magic user with range and a little brains. Transmute him into a rabbit, trap him in a hypercubic arena, stop his heart with voodoo, etc etc. As long as you know your target, and ideally have some kind of sympathetic link, he's hosed. For preference, Senex or Porthos Fitz-Empress (from Mage: The Ascension) would be my go-to here, but Doom could do it as could dozens of others. Professor X. Superman, or any of the dozens of Supermanalikes out there. Flight, eye beams and Flash's idiot tendency to stop and mouth off are probably enough to do the job. Silver Surfer Invisible Woman Plastic Man (and/or Mister Fantastic) Mayyyyyybe Classic Speedball, because of the way his power works. You get the idea. I can keep going. Give me a mid to high tier character with cause to take down Flash and I can probably come up with a way they could at least ruin his after-dinner plans. If it's Bloodlusted Flash then the list is a lot shorter, but there's still a decent lineup that can wreck him.

Gale wings Talonflame with aerial ace. Gale wings would make Talonflame go first and aerial ace wouldn't miss.

Zoom in the comics?

TAAAARRRKKUUUSSSSS Also I previously said Super Tengen Toppa Gurren Lagann. You "countered," it, but, I thought of something. Super Tengen Toppa Gurren Lagann is 52.8 billion light years tall. This makes it about 58% the size of the universe, which spans 91 billion light years. After transforming into its drill form, its size is multiplied immensely, since its Super Tengen Toppa Giga Drill is at least ten times longer (528 billion light years), and about four times wider. This gives it a cone area over 180 times the size of the Super Tengen Toppa, and a multiversal scale the size of over 100 universes. No matter how fast the flash moves, STTG will hit everything at once. "Flash can phase through it." And go where? No matter where he goes he would be inside of a god's drill. But whatever, you make your own set of rules so that you can never lose, making this conversation no longer fun lmfao.

Galactus because he existed before the Big Bang and other space magic

Han Solo he will shoot first

Spiritomb with wonder guard. Unless the flash can use a fairy type attack (which he couldn't as he's a human) he cannot deal any damage to spiritomb.

I feel like you made the rules completely unfair and 500% in your favor. Yet you were still beaten.