Again for what seems like the five-thousandth time, I said the explosive arrows are a bad idea.
Im not saying the explosive arrows are an idea that would be good (as mentioned above), but I will say that if they did exist, they would be fairly expensive, maybe a half stack of gold. I dont know, I just like shooting at eggs...
Also, the explosive arrows wouldnt be able to break obsidian, or at least not well. We already have TNT, and if you are smart you can make a TNT cannon that can blow the obsidian on an egg to bits.