Answer:
In a tunnel of darkness lies a beast of iron. I can only attack when pulled back. What am I?
I am a ship that can be made to ride the greatest waves. I am not built by tool, but built by hearts and minds. What am I?
It's red liquid but not liquid and it's not red. What is it?
You kick me, you punch me, and you beat me up all class. When you leave, you don't even say thanks for allowing you to beat me up. What am I?
One simple click, one simple flash. A piece of memory, for years I'll last. What am I?
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.