Bigger Than You Think, a riff on both Italo Calvino's Invisible Cities and XKCD's Click and Drag comic, is a new CYOA/parser-based IF hybrid by Andrew Plotkin. It was created for a fanfic gift exchange at Archive of Our Own. BTYT uses keywords that the player can type in or click on to use, and even an inventory that is always displayed at the top of the screen, along with the word "start", which is the keyword that begins a new playthrough of the game.
BTYT is about exploration, not just of the cavern the game starts in, but of different worlds, other lives, potential futures, alternate realities. This is highlighted by the way the inventory works: instead of limiting the player to things and ideas that they have picked up in one playthrough, the inventory is designed to work across multiple playthroughs, so that something you picked up in one is available to use in another. Contrariwise, once something is used properly in a playthrough, it stays that way for all playthroughs afterward (to pull this off, the game makes use of an autosave function, I think through Glulx's ability to write to an outside file). It is literally impossible to beat the game in a single playthrough; too many objects, too many ideas are in dead ends, and BTYT smartly makes use of this fact to call attention to what this might suggest: Perhaps merging realities, or reincarnation, or maybe just different stories that got smooshed together in the telling.
Stories, after all, are a part of BTYT's makeup, as the game is framed as a tale told by Marco Polo to Kubla Khan, a device inspired directly by Invisible Cities. There's references to stories throughout as well, mostly through the traditional CYOA intonations along the lines of "Your story must end here," but also through at least one case of recursive storytelling (I am thinking here of (Spoiler - click to show)the monk, and the tales of the lost cities you can access through him). What I found most compelling, though, was the ending: (Spoiler - click to show)at the end, Marco Polo stops his tale just short of revealing one last mystery to the Khan, telling him to get off his duff instead, although not in so many words. The player, who is heavily identified with Khan ("I did not undertake this journey, these discoveries! You did, o Khan. Always, it was you."), is too the recipient of this message to do something real now that the story is done. The fact that Marco essentially leaves the story to Khan to complete is, in a fan-work, a perfect detail, almost an invitation to create. I'm not lying when I say it was a big motivation for the writing of this review.
Bigger Than You Think is not a perfect game. There are too many times when figuring out which item to use in which situation can be a frustrating exercise in finding something you haven't done yet. And it's not always clear whether there is something you can try (though to its credit, BTYT mostly gets this right). But the worlds are dazzling, and the prose is pure Zarfian beauty. It's definitely worth your time to give this a look.