10 Worst Things That Ever Happened To Deadpool
6. Absorbing Another Person's Voice Into His Head - Deadpool (2008) #1
The start of a new Deadpool comic run in 2008 began with his regeneration power being pushed to its limit after he and a fellow immortal Madcap were reduced to ashes by the mighty Avenger Thor's lighting. The regeneration factors of Deadpool and Madcap activated at the same time, fusing the pair into a single being with Wade getting his body back, but also gaining two voices in his head, Madcap's and his own internal monologue.
These pair of comic book text boxes - one in white and one in dark yellow - would constantly talk with Wade inside his head, offering helpful insight or just comedic observations that were meant to be more for the reader than for Deadpool himself. This went on for years until eventually Madcap was released from his mind and regenerated into his own body.
And for the extraordinarily long time that he was in his head, Madcap and Wade's constant bickering brought them both to the point of insanity, making it difficult for the merc' with a mouth to have any time at all alone to himself, as he was always with two more people that never shut up, and that he could never get rid of.