Answer:
I am good at concealing what's real and hide what's true. Sometimes I bring out the courage in you!
I am the type of room you cannot enter or leave. Raise from the ground below I could be poisonous or a delicious treat.
With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?
I can run but not walk. Wherever I go thought follows close behind.
What can you catch but not throw?
No matter how little or how much you use me, you change me every month.