By any measure, Daredevil is one of Marvel's most popular heroes, as his parade of comic books, a movie and a Netflix series attests. While Matt Murdock generally suits up as a street-level hero whose abilities mainly (but not exclusively) make him a threat to street-level bad guys, he has briefly changed in a big way on occasion.
The Man Without Fear gained unbelievable cosmic powers - as well as his eyesight - after the being known as Captain Universe possessed him in "Sensory Overload," a story in 2005's Captain Universe/Daredevil #1 by Jay Faerber, Juan Santacruz and Daniel Acuna.
Captain Universe is a powerful heroic entity and the protector of the abstract cosmic being known as Eternity. It's not a character, per se, but rather a sentient force that requires a host to merge with in order to fully function.
Once any given host bonds with Captain Universe, the host in question gains the Uni-Power, which not only grants a wealth of high-level powers like superhuman strength, speed, durability, flight, telekinesis, X-ray vision and a psychic awareness of imminent threats. It also enhances the existing powers and abilities of said host to absolutely extraordinary levels. For example, if a character who could teleport over a distance of a few miles was possessed by Captain Universe, the Uni-Power would likely enhance their ability to the extent that they could teleport across galaxies.
Since its first appearance on-panel in 1979's Micronauts #8 by Bill Mantlo, Michael Golden, Bob McLeod and Carl Gafford, Captain Universe has possessed the likes of Doctor Strange, the Hulk, Spider-Man, Gladiator, the Silver Surfer, the Juggernaut, Deadpool and a bunch of regular civilians.
When the Force possessed Daredevil in 2005, it was in part of a five-issue story that also saw the Hulk, X-23, the Invisible Woman and the Silver Surfer get their own stories in which Captain Universe possessed them, each being sought out by the entity for a unique reason. And in Daredevil's case, Captain Universe merged with him in order to utilize Matt Murdock's skills as a lawyer.
While the being was bonded to the Hulk in a previous issue, an invisible A.I.M. agent killed a man named David Garrett. Garrett's business partner, Gilbert Wiles, who was researching the Uni-Power at the time, was blamed for his death, and Captain Universe wanted to clear Wiles' name with help from Murdock.
Through bonding with Murdock, the Uni-Power restored the superhero's vision and enhanced his superhuman senses to the extent that he could barely function - hence "Sensory Overload" being the issue's title. In spite of all the benefits the Uni-Power provided Daredevil with in his fight against evil-doers, the inadvertent and unavoidable negative effects gave him no choice but to expel it from his body, resulting in him reverting to the street-level hero that Marvel fans know and love.
Murdock went on to prove Wiles’ innocence in court, before suggesting to the Captain Universe entity that it should look into A.I.M.’s findings with regards to its situation, in order to ensure the sensory overload issues he experienced wouldn't be repeated with other hosts in the future.
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