it looks like an overgrown zucchini, but seems to have e the firmer skin of a winter squash? It's huge, and there are a bunch more on the vine. I didn't harvest just in case it is a winter squash and should stay on the vine.
Thanks!
Yes, where did the seed come from? What squash did you grow last year?
It does look like a cross. Squash are notorious for that, it's hard to save pure seeds because they cross-pollinate so readily. Since squash have separate male and female flowers they depend on pollinators to carry pollen. Some of those pollinators can fly a mile with some different pollen. I once saved Delicata seeds, a winter squash, just to see what I would get. I got some strange squash the next year, not sure what it crossed with. It made a good tasting winter squash but did not save worth a darn. Here's what it looked like.
If you don't know what it is I'd try a young one as a summer squash just to see how it does. And after it matures I'd check it out as a winter squash, you never know.