Which universe of geniuses have impressed you the most? Any and all feats count.
On the Marvel side you have
Amadeus Cho
Reed Richards
Dr. Doom
Forge
Hank Pym
High Evolutionary
Tony Stark
Kang
Bruce Banner
Immortus
Hank McCoy
Mr. Sinister
DC
Lex Luthor
Will Magnus
Alexander Luthor
Brainiac 5
Mr. Terrific
The Chief
Rip Hunter
Ted Kord
Steel
Ray Palmer
Bruce Wayne
Dr. Sivanna
Ivo
TO Morrow
If you're talking about geniuses then Forge really shouldn't be on the list. He can build just about anything but that doesn't mean he understands what he's building. For example he can build the most advanced time dilation device in the world and fit it on a pocket watch but he won't necessarily understand the science behind it.
edit: btw Miracle machine on Braniac 5 is essentially insta win on feats list. Also Superman should be on this list with some of the crap he's pulled over the years via tech... Yeah lets make a helmet that makes two supermen.... Brilliant.
The alien being used reeds knowledge of the multiverse to create it...
__________________ Quotes from Hia8:
"I claimed that the science is sometimes faulty."
"You don't understand. This is fiction. That means none of this stuff really happened."
"There is no writer to purposely ignore a character's natural ability just because it suits the story."
"in some cases because the writer knows that Character A will dominate Character B easily and refuses to allow this to happen for the sake of the story."
which isnt the exact same thing alexander did. brainiac 5 also created a map of the multiverse and placed within starmans costume. b5 is on reeds level, imo.
This made made chuckle. "I didn't want to include any ubers, but I included the dude who resurrected the multiverse and single-handedly changed DC continuity as we know it."