Echo is a stealth video game released on 19 September 2017. It was developed and published by Danish indie studio Ultra Ultra. The game takes place in a planetwide palace that creates echoes of the player and teaches them the actions of the player. The game was not a financial success and was the only game released by Ultra Ultra before it shut down. Echo is a science fiction story in a future where advanced technology has been used to colonize distant planets. Most societies are governed by advanced artificial intelligences. En is a woman from a "Resourceful" group of genetically modified humans. Her AI companion London pilots her ship and frequently argues with her because she was involved in a violent incident that led to the death of his former human partner Foster.