Bruce Dickinson has enjoyed "playing like children" away from the strictness of Iron Maiden.
The 65-year-old rock legend has reunited with Roy Z on 'The Mandrake Project' - his first solo album since 2005's 'Tyranny of Souls' - and he's loved getting to throw everything at the musical venture, and its accompanying comic book series.
He told Metal Hammer magazine: "It's not that Maiden albums aren't fun, but we don't get to play like children.
"[Iron Maiden bassist and songwriter Steve Harris] is very specific about stuff: things have to be done THIS way.
"It's the way we've always worked, and it's obviously worked well.
"Whereas me and Roy, we're like kids in a sandbox going, 'Hey, look at this, Zee, I can put this toy up my nose!' It's just energising."
That proved to be the case on new track 'Resurrection Men', which sees Bruce trying his hand at the bongos.
He added: "Dave [Moreno, the drummer on 'The Mandrake Project'] has this big box of stuff to bang and shake.
"So I started grabbing things: 'That sounds nice, let's have a go! Bongos? Brilliant' "
Despite being known as the singer of the 'Run To The Hills' group for decades, Bruce also turned to the guitar on this solo album, even delivering a solo on 'Face In The Mirror'.
He quipped: "It's minimalist to say the least. I couldn't tell you a pentatonic scale from a gin and tonic.
"I don't rate my guitar playing at all, but if it sounds good, I like it."
Meanwhile, Bruce also reflected on his interest in all things mystical and strange, as he looked to find an escape during his early teens when he was unhappy boarding at Oundle public school in Northamptonshire.
He said: "It's my 14-or-15-year-old self, being at boarding school and feeling totally powerless. And thinking, I'm going to read books about the occult, maybe it'll help me out."
