Answer:
Die without me, never thank me. Walk right through me, never feel me. Always watching, never speaking. Always lurking, never seen.
What turns from red to black as soon as it touches water?
Soldiers line up spaced with pride. Two long rows lined side by side. One sole unit can decide, if the rows will unite or divide.
The man who invented it doesn't want it. The man who bought it doesn't need it. The man who needs it doesn't know it. What is it?
Look into my face and I'm everybody. Scratch my back and I'm nobody.
Special abilities and brightly colored underwear are all you need to be one of these.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?