The singer is dungeoneer Martin from Series 3 Team 11.

This minecart's not the first cart broken

On rides down into Level 3

But I could be, you know

The first to win since Series 2

Above, I'm just a Toole who's willing

To float around and shout out "Boo"

But down here, I will flee

When a hobgoblin's there in view

I'm helplessly below Level 2

But now there's nowhere to hide

A cat shoots from either side

I'm quick or I'm dead

Helplessly below Level 2

Helplessly below Level 2

Helplessly below Level 2

The dragon's saying, "Fool, do better"

Morghanna's laughing as I go

I step with bravery

As that's what Merlin said to do

I hope that means that I'm getting through

But now the end comes along

'Cause I got a riddle wrong

I'm zapped in the head

Helplessly below Level 2

Helplessly below Level 2

Helplessly below Level 2