In Star Trek Beyond, what was Krall’s former name?

In Star Trek Beyond, Krall’s former name was Balthazar Edison.

Edison was a human and former military commander who became the film’s villain after being stranded on the planet Altamid. He had commanded the USS Franklin, an early starship launched before the Federation was fully established. His resentment toward the Federation grew after he and his crew were abandoned.

On Altamid, Edison used alien technology to extend his life by draining the life energy of captured beings. The process transformed him physically and led him to adopt the name Krall. He then built an army and planned an attack on the Federation starbase Yorktown.

Krall is played by Idris Elba, whose heavily altered appearance concealed the character’s human identity for much of the film. John Harrison is the alias used by Khan in Star Trek Into Darkness, while Alexander Marcus is that film’s Starfleet admiral.