Answer:
By myself, I'm practically nothing. Worthless as a leader, but when I follow a group, their strength increases tenfold. What am I?
What gets sharper the more you use it?
I am an odd number that become even when beheaded.
u always follow me but I am rarely seen
The 8 of us go forth and not back to protect our king from a foe's attack. What am I?
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.