Wheelbarrow.
I am two-faced but bear only one. I have no legs but travel widely. Men spill much blood over me. Kings leave their imprint on me. I have greatest power when given away, yet lust for me keeps me locked away. What am I ??
For some, I am used to get around. I never even touch the ground. Sometimes I fall in a large open tank and sometimes I float in the air and then rise. What am I?