For the Origin-Zero Mecha contest, I have designed this modular backpack so you don't have to print multiple backpacks for your Mecha. I have added a wing attachment, a jetpack attachment, a flag attachment for the backpack, and swords with holders, you can see these accessories in the images above ⬆️. To get the accessories off of the backpack, you can use a fingernail to push the tiny ledge sticking out from the backpack. Feel free to design your own attachments to go with this. The tolerances might be tight if printed in certain filaments, though I have only tested PLA basic so far so you can give feedback if you are using a different filament. If there is anything that you feel could be improved, feel free to contact me. Have fun with the model!