Unarmed – Best of 25th Anniversary is the 25th Anniversary celebration album by the Germanpower metal band Helloween. It is a compilation of re-recorded versions of Helloween songs in an acoustic/symphonic style. It includes a 70-piece Prague Symphony Orchestra performing "The Keeper's Trilogy", a 17-minute medley consisting of the songs "Halloween", "Keeper of the Seven Keys" and "The King for a 1000 Years". Many guest musicians are featured on the tracks.
It's just like we've been asked what to do [regarding their 25th anniversary], if we're going to do fine remakes or re-masters, but then sell the old stuff people get at home anyway just a slightly different sound, it wouldn't make any sense to us so we just wanted to give people something new. [...] It was interesting and fun to play a bass like this that you can hear on that record because I never did this.
The vocalist Andi Deris, however, panned the album in a 2015 interview, saying he never liked the idea of doing it and that the record company "raped" the band to do it. He commented,
You know, if I would like to have an acoustic album, I would have bought an acoustic guitar in the first place. What did I buy? An electric guitar. So what is this for me? Rape. I didn't like it at all. It was nice to sing this shit and actually show myself that I'm capable of doing that, not hiding behind the metal music but being the main instrument with the voice and front of everybody else. But that's it, that's it. I don't like the idea of being a metal band and then put out acoustic versions of your music. I would have done that in the first place if that would have been my intention of the music my heart beats for, but it's not.