Answer:
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
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.
A mother had five boys Marco, Tucker, Webster and Thomas. Was the fifth boys name Frank, Evan or Alex?
Often held but never touched. Always wet but never rusts. Often bits but seldom bit. To use it well you must have wit.
A time when they're green. A time when they're brown. But both of these times, cause me to frown. But just in between, for a very short while. They're perfect and yellow. And cause me to smile.
What is so fragile that saying its name breaks it?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?