According to a posting on the IRON MAIDEN fan site MaidenFans.com, MAIDEN guitarist Adrian Smith has ended years of fan speculation by revealing that the 2000 album "Brave New World" featured leftovers from the 1998 CD "Virtual XI". Asked in a 2003 interview to identify the four songs that were written during the sessions for "Virtual XI" that ended up on its follow-up, Smith said "'Nomad' is one of them. The others are 'Dream of Mirrors', 'Mercenary', I can't remember the fourth one."
The interviewer, Kevin Lomax, had the following to say about the issue: "I did the interview in the Sanctuary Music London after a brief preview of the 'Dance of Death' album. The interview was with Adrian Smith. I had fears before asking that question, because maybe Steve Harris might have said 'Don't tell.' Anyway, I asked and he said that 'Nomad' (which I'm surprised), 'Dream of Mirrors' (not surprised in any way!) and 'Mercenary' (the worst song of 'BNW' from 'Virtual XI', that's obvious!) were from 'Virtual XI'. He couldnt remember the fourth one. And I asked if 'Blood Brothers' could be one of them, because it has similar melodies [to] 'Educated Fool'. He said no, it was not. He thought for a while but he couldnt remember the fourth. (Maybe didnt want to answer)
"I had a quick chat with [former IRON MAIDEN singer] Blaze [Bayley] in Istanbul, before his performance in Rock The Nations Istanbul. (Where he did a duet with Paul Di'Anno) And in that chat he said that he had written some of the lyrics of 'Dream of Mirrors' but Steve didn't give him a credit for that in 'BNW'. When he saw that he [was a bit frustrated]."