What one character from Marvel/D.C. would most change the other comic landscape?

Think of one character was "transplanted" into the other's universe and was introduce naturally intot he universe. In other words, the character and their origin or an alternate version of their origin exists in the other universe in a way such that they were "born" into the universe. Which character's existence would bring about the most change with their introduction? My pick: Frank Castle in D.C. universe. Why? The Joker and all the other little shithead psychopaths that Batman has allowed to commit mass murder would be bloodstain in the past.

The Flash, Nobody on Marvel earth has seen anything move like him, even Quicksilver and Speed Demon are a distant 2nd place.

Put him on the Avengers and Stark will go crazy trying to figure out the "Speed Force"

Impossible Man

Originally posted by golem370
Impossible Man

He barely does anything in the MU

OK Celestials along with Eternals Deviants

Originally posted by Blue Area Vet
Think of one character was "transplanted" into the other's universe and was introduce naturally intot he universe. In other words, the character and their origin or an alternate version of their origin exists in the other universe in a way such that they were "born" into the universe. Which character's existence would bring about the most change with their introduction? My pick: Frank Castle in D.C. universe. Why? The Joker and all the other little shithead psychopaths that Batman has allowed to commit mass murder would be bloodstain in the past.

Good point. Frank would more or less eradicate street crime, in places like Gotham and Bludhaven. Arkham would be a ghost town.

Originally posted by Scoobless
The Flash, Nobody on Marvel earth has seen anything move like him, even Quicksilver and Speed Demon are a distant 2nd place.

Put him on the Avengers and Stark will go crazy trying to figure out the "Speed Force"

lol, I like the last part of what you said. Stark would find a way to harness it eventually.

Originally posted by golem370
OK Celestials along with Eternals Deviants

What ONE character.

Doom!!!!!

Originally posted by Newjak
Doom!!!!!

You now, I amost want to change my answer now. The only reason I didn't put Doom is because as much as a presence as he would have, what ex.....wait, nevermind, you are right. His pursuit of the Antilife Equation alone would be game changing. Also, Doom would put a lock on the Orange Lantern. And oh yeah, magic is stronger in D.C., Doom would be a beast.

Apocalypse

Originally posted by golem370
Apocalypse

The problem is there are no mutants.

With D.C. having such a strong magical presence, someone who could really do some damage would be Desak.

Frank Castle in Gotham. Id buy that.

Flash to Marvel. Thanos to DC.

Originally posted by Astner
Flash to Marvel. Thanos to DC.

Thanos would make epic storylines and would conquer the universe and put it back, but would he actually change the landscape? I don't think so.

Originally posted by Astner
Flash to Marvel. Thanos to DC.

Agreed on the Flash. Not sure about Thanos, though. I'd go with the Sentry.

Blue Marvel at DC. An earthling hero more powerful than Superman. Game changer.
Wonder Woman at Marvel. A top tier heroine AND not a copy of a male hero. She'd polarize the MU women, give them a rallying point.

Originally posted by Juk3n
Frank Castle in Gotham. Id buy that.

Valeria Richards to DC.
The Shade to Marvel.