Once upon a time in a land far, far away…
Baron Von Sankt Troffembach invaded with a force of three thousand Mecha. The scouts encountered no resistance at all, and the giant Titan robots and their support mechs gathered in one massive, terrifying force at the Grey Forest in preparation to rolling into Kapfenberg.
The desperate Mayor summoned the Witch Queen, Marta Esmeralda, for aid.
At sunrise, a fog of greenish-blue arose from the ancient swamp and the invading force began corroding, quickly enough to be visible. Marta’s version of WMD was a cloud of 2,2-pyridinium dipyridyldisulfide chlorochromate, a corrosive agent which violently attacked and dissolved the giant mecha completely.
You can see all that’s left. The toxic blue fog cloud that never retreats and the rusty water marking the graves of hundreds of members of the invading force.
The war was over, but dispersion, stray winds and groundwater seepage returned Kapfenberg to the Bronze Age.
Inspired by this week’s Monday Finish the Story prompt:
ParkInkSpot 
That first line doesn’t help anyone’s story. Some tropes should be allowed to quietly expire.
Of course, what do I know? I write with mecha and witches.
I agree about that first line, it is ever so cliché!
But I enjoyed your story, for it shows that you have a great imagination to link it to the prompt.
WMDs always have a down side – for both sides. A victory, but at such a cost.
It’s like a wish. You may get exactly what you asked for, but… [there must always be a but]
I just thought about what magic would use for a WMD and what the fallout would be. Rusty-red water, hmmm…
What a great take on the photo prompt! I loved this story Dave! What an imagination! See you next week? I hope so! Be well… ^..^
Good story and use of the prompt, Dave. The witch queen seems to have had a knowledge of chemistry. Well done. 🙂 — Suzanne