This has one of those guest performances that I'm sure was supposed to be an entertaining and amusing character piece, but the pirate and all his low-key "Ahhrrr"-ing got on my nerves but quick. On the plus side, it has a rather interesting 19th century alien abduction backstory that seems ahead of its time, and it has some robut-on-space monster battle action. I also like the way a lot of this isn't explained -- exactly why did the blob want the future-telling gun, and how does it hold it? It's just left up to the viewer's imagination.
But can someone please explain to me why Dr. Smith was given absolute control over the robut again? Did no one at Mission Control think this was a bad idea?

Salmi's hammy, over-the-top performance is just perfect as the sly, but lovable Tucker making him one of the best of the LIS villians/aliens in the series. Problems with this episode include a slow story-line and that glowing Blob Creature which joins the Bush and Sand Creatures from previous episodes as cheap, unimaginative creations which threaten while the music pounds us over the head.
Still a good one, though.