It's not exactly a spoiler that Magica has been a fairly dark show (and if it is a spoiler, it's the kind of spoiler you should know). However, episode 10 leaves me feeling more optimistic about the show having a happy ending, not because of anything in the plot of episode 10 but instead for thematic and structural reasons. Explaining more requires spoilers, so here they come.

Episode 10 covers Homura's backstory, where we learn that her wish is to protect Madoka and that every time she fails to do so her power over time causes her to loop back in time (to the start point of the series) to try again. This entry has a good rundown of the resulting timelines.

By explicitly covering this background, the story creates a major point of tension: will Homura succeed? There are three possible resolutions that I see:

• Homura does not succeed, but she loops back to try again. This would probably be an unsatisfying ending since it doesn't actually resolve anything and makes the entire series into just another one of Homura's time loops, no different than the ones before it.

• Homura fails permanently (she ends up dead or powerless, unable to loop back in time to repeat things). This would be a very grim end and make the overall theme of Magica be about the inevitability of fate; Madoka is simply fated to be a mahou shoujo and fall, and nothing Homura does can change that.

  (If anything, everything Homura has done to date seems to have made Madoka progressively more powerful. She starts out in timeline 1 as an ordinary mahou shoujo and ends up in timeline 4 as almost all-powerful.)

• Homura succeeds (probably in some bittersweet way; I expect her not to survive).

As mentioned, the first option feels fundamentally unsatisfying. The logic of making a story is that you focus on the climactic point; the only way to make a 'and everything resets to try again' ending be even vaguely a climactic point in the story is if Homura resolves to never give up even though it's hopeless.

The show could do the second option, but it feels wrong to me; it would be really grim without following what I think of as the normal model of a tragedy. (I think that it would be a Faustian tragedy if we did not know Homura's backstory, because then the story would remain entirely focused on Madoka and her choice.)

Thus, I am cautiously optimistic that we will get the third ending in some way; it seems like the most satisfying way to resolve the tension that episode 10 creates, and the show went out of its way to create that tension.

PS: I suppose a fourth possible resolution is that Homura fails but Madoka convinces her to go on to live instead of spending the rest of her life in a time loop. The problem with this is that we already know Homura doesn't have a pleasant life ahead of her regardless; like all mahou shoujo, she is doomed to either death or becoming a witch.