I don’t know if there are open source hatetris available, but in my case it was an assignment so that wasn’t an option.

If i build something from scratch it doesn’t really matter that it “could have been” built on open source. And in any case, it might be perfectly legal and in accordance with the license to do what OP did, I’m just saying it’s bad form. Making a minor tweak doesn’t make it “by you”. It just doesn’t.

And this is not medicine and lovetris doesn’t save any lives, so I’m bot sure it’s relevant.