You can hear it in Lee Hoy's voice, the defiance, even over his warm, rounded, north-east accent.
It's hardly surprising. After all, if you're stepping into the octagon to fight people who are only visible to you as a blurry outline, you need it.
This is Lee's passion, MMA, and being unable to see due to congenital toxoplasmosis, a rare condition he was born with, hasn't stopped him. He regularly takes on, and beats, sighted opponents. To some people he might be considered the real-life Daredevil, I suggest. "Some people read too many comic books," is the response.
After suffering bullying throughout school, and wondering to himself how he'd ever be able to fight back without being able to see, it all came to a head one day a few years ago for the 28-year-old from South Shields.
"I had one day where I thought, 'I need to do something'. I was passed on to Fighting Fit, the team I've been part of for three years now, and I came and started to train with them, learning skills once a week. I really loved it, and started doing more and more to the point where I'd train Monday to Friday, double classes."
You almost get the feeling listening to Lee that he downplays his achievements - always quick to heap the praise on to his team and the support from people around him. But the personal determination is clearly there. "All I really do is wake up and think to myself: I could take the option to let the sight issue defeat me, and go that way, but why should I? I tell myself I will do this."
Lee's dad, who passed away 10 years ago, was a semi-professional boxer in his time, and the only moment a tone of regret creeps into Lee's voice is when talking about his father.
"I kind of wish I got into this a bit earlier... but everything's got its time. I'd like to think he's looking down on us proud. I think if he was here he'd definitely be proud."
It's easy when confronted by humans like Lee - who are seemingly doing extraordinary things - to see them as separate. To imagine that they were somehow born with a little extra motivation than most people, or without the capacity for self-doubt. But Lee puts everything he does down to "trying".
"Everybody gets those days, and if people tell you they don't they're not telling you the truth or they don't want to admit it, because they might feel weak. But that's what makes you stronger. When you get days when you feel 'what am I doing here, why am I even...'" Lee says, as his voice trails off... "But you push yourself through it. Then you realise, actually, I can do it."
Lee often enters MMA competitions and performs well, despite only ever being able to see the outline of his opponent. "Because MMA is not just about punches and kicks, it's about grappling and wrestling, as soon as I get my hands on a person that's where for me it works out more.
"Again though I don't think 'oh I've got visual challenges so I can't do certain elements'. I put the work in. I try and do every different part of MMA."
Most of all Lee hopes his example can help people from all backgrounds achieve what they want to do.
"This is now where I'm very grateful to iD Mobile, to have the opportunity to put my story out there and show people whether you've got a disability or not, you can do it. You can be a fully sighted person and have a goal to own your own business, and you might think you can't do it. But until you try, how do you know? No matter what you've got going on, you have to try. Whatever you want to do, do it."
Lee Hoy from Fighting Fit MMA club, South Shields, features in iD Mobile's new documentary series #DoYourOwnThing. The series celebrates individuality and diversity in his story of being an MMA fighter. The videos are available to watch on Facebook, the iD Mobile YouTube Channel and idmobile.co.uk/doyourownthing/blind-fighter