Strange artifacts

Hi all,

I am pretty new to blender and I am curious what could be that red artifacts that is at the back of the car?

I did not have this when i was in the viewport. Only when it started to render, then it is there.

I’ve rendered in it cycles.

Thank you!

Looks like optic denoiser artifacts, disable denoiser and look it it changes. Try opendenoiser and/or increase samples.

Sure, thank you!

Does the caustic affect this as well?

Yes, reflections/caustics are the origin.