The 22-year-old left-back, who has been capped at various youth levels for Spain, has put pen to paper on a three-year deal with Villa. The news of Luna's arrival comes two days after the midlands outfit announced they had sealed the capture of Denmark striker Nicklas Helenius from Aalborg.
Last week they brought in another Denmark international, centre-back Jores Okore, as well as Holland Under-21 midfielder Leandro Bacuna, and the week before that Villa confirmed they had agreed a deal to sign Bulgaria midfielder Aleksandar Tonev.
Luna told the club’s official website: "I've always believed that I could play in the Premier League and to have this opportunity with a club as historic and huge as Aston Villa and with a manager (Paul Lambert) who is building a squad of young players with great prospects is tremendously exciting for me.
"I really can't wait to get started and to play my first game. I have a great expectation coming here.
"The manager explained to me that it is a young squad but also one with good experience and everyone is hungry, everybody wants to succeed here.
"This is perfect because I am keen to make progress myself and I want to be part of this."
He added: "Obviously, I have watched Premier League games and I am totally aware of the pace of the game and that the challenge is to constantly be at the maximum and top of your performance.
"There have been many good and great players from Spain who have come here and succeeded and I know I can adapt my game also.
"The quality of football in La Liga is also respected everywhere and this is why I believe I can do well in the Premier League."
- Sports & Recreation