The short answer is, "Yes, it is fine to use previously created assets". The longer answer is "be reasonable about it". If the pre made assets you use make up the entirety or a major part of your jam submission, that is not ok. If you have a script or two that are pretty standard or will help you with a feature or two, that is fine. There will also be a place for you to write a note about this when you submit your jam entry.
The rules say "
- Asset Usage Guidelines
- You are free to use any assets (Sound, Music, 2D or 3D Art, Fonts) which you have the legal permission to. For example, asset packs purchased on the Unity Asset Store.
- If you do use previously created assets, say so in your game’s submission
- Teams who create their own assets as a part of the jam will be given a slight competitive edge from the judges. We don’t want to exclude anybody from the jam who can’t find a team, but we want to incentivize our community to work together + form relationships!
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