Gaming

Final Fantasy 14.

Hear me out. It is an MMO with a very regular update schedule, so regular that you could set your calendar by it and the only thing that has ever disrupted it in the last 10 years was COVID. You are guaranteed 5 major patches per expansion and 5 minor ones. Each expansion gets a fixed raid series (12 savages, 7 extreme trials). This is in top of continuing support for about a dozen major systems like crafting events, the blue mage minigame, 2 or 3 new systems for the expansion, new main quests, etc. I know for a fact that I will have enough content to tide over the year.

This is not a hypothetical. This actually happened when I moved into my new apartment during COVID. FF14's content additions make WoW's look pathetic. The only drawback is if you don't like the anime style and that is not a problem for me.

EDIT: The reason I didn't name WoW is because 1) WoW expansions are not consistent and there is severe variance in quality. It might be great today, but I can't guarantee liking it in six months. 2) WoW patch cycles can take ages. This is fine if I can switch to playing something else, but OP specifically says I cannot play any other game or leave the dark room.