Played this and Episode V back to back, so I can't really tell my feelings for them apart and at this point I feel like it's kind of sloggy and picked back up again in the fifth episode. Here's it's a this is your three things to do, one of them will be a pattern puzzle again (though much better and more interesting), a puzzle that actually uses time travel and one where I just broke things and gave broken things to someone.

Once those were out of the way, Marty and Doc have an argument where Doc drops some truth bombs on Marty (at which point I was quite keen to see where it was going to go), but no... doesn't go there.

My main beef with this one's story though (which is actually a beef Episode 3 but didn't occur to me until Episode 4... I'm not clear on why Doc disappeared from the Delorean at the end of Episode 2/start of 3 when whenever Marty has gone back to the future even if that future is different but he still exists, he doesn't forget going back in time. And Doc never invented the Delorean so doesn't that cause a paradox where the Delorean itself should have faded from existence in 1931?

Probably just overthinking something which shouldn't be thought too hard about.