Answer:
Searing 'cross the pitch-black skies I scream in celebration Yet moments later my outburst through I am naught but imagination.
I'm a ruler with 12 agents. Half of them work in the darkness. Who am I?
After you go through a fall, I will take over. All life will stall, or at least grow slower. What am I?
What has feet and legs, and nothing else?
If you have it, you donβt share it. If you share it, you donβt have it. What is it?
No matter how little or how much you use me, you change me every month.