While merging, if you pick a value below 0 or above 1, you will extrapolate rather than interpolate, which will allow you to create merges that lie outside of your usual "gamut", so to speak.
It can be achieved by altering some lines of code in "ComfyUI\comfy_extras\nodes_model_merging.py".
"min": 0.0, "max": 1.0,
"min": -1.0, "max": 2.0,
It should look like this:
(I've also attached an already edited version of nodes_model_merging.py in this article.)
This will unlock new opportunities for experimentation. Don't be afraid to save a model that makes fugly ass deep fried images. In fact, a pinch of one of those can add a lot of flavor to your next interpolation!
Little trick I learned on Artbreeder. (Yes, even now, I spread the good news of "extended sliders" 😇🙏)