- "A few of the Faith Militant's more... militant members even scaled the walls of the castle and would have slain the king and his family had a knight of the Kingsguard not intervened."
- ―The High Sparrow.
Mychal was knighted by Lord Commander Serwyn Errol at the age of 23. When members of the Faith Militant scaled the walls of the Red Keep, Mychal was able to keep them from killing King Aenys and his family. However, Mychal died in the process.
He has an entry in The Lineages and Histories of the Great Houses of the Seven Kingdoms, which notes the fact that he, along with all of his ancestors and descendants were born "black of hair".
In the books
In the A Song of Ice and Fire novels, there is no character named Mychal, either of House Baratheon or any other house.
In Season 1 of the TV series, Ned Stark looks through the pages of The Lineages and Histories of the Great Houses of the Seven Kingdoms, but for the visual medium of television the prop had to be filled in with other pages of writing beyond the sections on Robert and Joffrey that Ned specifically read. Writer Bryan Cogman said that he filled in much of this by simply making up names or using in-jokes - and these aren't strictly canon. On the other hand, some of the details are accurate to the novels, such as information on the Blackfyre Rebellion, do match the already released novels.
One of the entries visible in the book says that one of Orys's sons died preventing an assassination attempt on King Aenys - the prop names this son Mychal Baratheon. In the books, a Baratheon by the name of Raymont Baratheon served in Aenys's kingsguard. It is unclear if this was behind-the-scenes information that George R.R. Martin shared with Cogman, or if he simply guessed that one of Aenys's Kingsguard may have died fighting off an assassination attempt in the Faith Militant uprising (the details of which weren't specified until some time after Season 1 was produced).
In the print material so far, it is unclear if Raymont Baratheon died defending Aenys during the Faith Militant's attack on the Red Keep. Moreover, it is not specifically clear if he was Orys's son or his grandson - only that he was the son of a "Lord Baratheon".