I submit to you this, select a random object within two feet of yourself. That object, hereinafter referred to as THE PENCIL, is almighty. Now, there are supposed to be three ways in which God answers prayer. Those are; yes, no, and later, as demonstrated here http://www.christianpost.com/news/three-answers-to-prayer-55396/. Ignoring for now the moral implications of not helping someone who is in pain when you have the power to reverse their injuries/damage, I'll move on to the main point. THE PENCIL is an all-powerful entity, it knows your every thought and hears your pleas. THE PENCIL will answer your prayers to it with yes, no, or later. Those answers encompass every single possible outcome.
Yes, your wish will be granted.
No, your wish will not be granted.
Your wish will be granted whenever I feel like it, bitch!
There's no way to not fall into one of those outcomes. So is THE PENCIL all-powerful? Why not? Pray to it, and in it's infinite wisdom it will decide to grant your wish or not. But at least it is possible to observe THE PENCIL.