Finishing everything off

"Just what the heck was that… I thought that the world was about to end!"

After a few moments, the two of us could finally communicate normally, without one side shouting and the other one trying its absolute best to understand the message.

"Allow me to introduce you to my new, slightly overpowered skill, doomsday series…"

I had to start explaining this new spell of mine in order to realise that I actually have failed to properly name it so far! Yet contrary to what one might think, it wasn't something that I could do so easily.

After all, this single spell of mine, costing less than a fraction of my total mana, was actually capable of not only obliterating several sage class monsters at once but actually changing the geography of the entire area by evaporating entire peninsula! How could I come up with a name for it so easily?

"Well, rather than keeping you waiting, I can just openly admit it. I have no idea how to name it."