I was reading Comic 10 and noticed that in Ryo's Lab is a battle machine with yellow legs. The questionable is that the Supernova (The only yellow battle machine in the era) was already on the battlefield. I thought for a bit and made some opportunities:
- There was planed to be a second Supernova.
- It was the prototype of the Supernova.
- It was just a artist's error.
Please note that the opportunities are just presumptions.
Write your opinions and own theories in the comment sections!
I would enjoy to read them and discuss with you! :)