As noted in the other reviews, Batman is Screaming is an early Twine game by Porpentine, interesting now in how it hints at some of the themes, tone, and imagery that Porpentine would develop in her later, more fully-formed games.
But this work is more than just an historical curiosity -- it's a really fun, gleefully grotesque, piece of interactive fan fiction. Porpentine totally captures the voice of the Joker but, like the best fanfic, introduces a scenario that would (likely) never make it past the DC editors or Warner Bros execs: (Spoiler - click to show)Batman has been trapped inside of some sort of bizarre ant farm; pieces of him have been slowly pulled apart while he still maintains consciousness and a sense of self that, I imagine, is deteriorating along with his bodily integrity.
This is a brief work that almost reads like a prose poem, given Porpentine's typical flare for evocative language and poetic images. Alternatively, as this is a work told from the perspective of the Joker after all, we could read this as an extended joke -- in which Joker gets the last laugh, of course. In either case, Porpentine uses Twine to parcel out the scenario in brief passages, both haunting and hilarious. This is a nearly linear story (with a couple tangents that circle back to the main thread), but the affordances of Twine are still well deployed. Plus, the purple and green color scheme is too good.