Simon Deimel's Enigma starts out like an off-kilter version of "Hello, World" for Inform 7.
You start in a room frozen in time, and the whole game plays out as the protagonist's experience of a single moment oriented around one decision(Spoiler - click to show): to shoot or spare your best friend. Starting with only immediate sensations, you must build a chain of association between memories and perceptions that let you come to a realization about the truth of the situation you are in.
Exploring a memory may let you perceive things more clearly. Exploring a perception may trigger a memory. On occasion, a threshold can be reached that allows a kind of breakthrough into new conceptual spaces. Sometimes memories or perceptions will be enhanced, providing a more connected impression over which to mull, so you must return to a topic to see how new scraps of information fit into it. The text is delivered in a fast-paced, heart-hammering style that seeps into your attitude and keeps you rapidly typing until you arrive at the conclusion.
There are really only two verbs that make a difference(Spoiler - click to show): 1) "examine" and 2) "remember" or "think about". If you somehow get lost, the "hints" command will offer specific topics for introspection. This is probably not a good thing to use as a first resort, but it's helpful on a second run through.
It's really quite remarkable that Mr. Deimel has managed to create such a compelling experience out of such a small range of action, and the extent to which he has achieved this speaks to his creativity in developing and executing the concept. While he notes in the post-game INFO block that the basic concept is not new, it was new to me.
From a technical standpoint, the execution is good but could use a bit more refinement to reduce repetition of certain topics and smooth the experience. As a player, it's sometimes clear that you have hit a dead end, but it's also difficult to ascertain which topic will advance the situation without resorting to hints. Perhaps a routine that would "auto-associate" previously-explored topics that have been updated due to new information after a certain number of turns?
On the other hand, the sense of urgently and repetitively reviewing bits of experience very much conveys the mindset of the PC, and perhaps it enhances rather than detracts from the play experience overall.
From a writing standpoint, there are opportunities for improvement(Spoiler - click to show)-- for example, it's not made at all clear what drove Tim over the edge, and this leaves the whole scenario feeling a bit forced. Then again, it's not always clear in real life, either, so perhaps that's intentional.
In addition, although I liked the writing style, some additional work to smooth out the line breaks when reviewing the scene would have greatly improved the impression of a fully completed and polished work.
Overall, a good comp entry and an enjoyable short work. I look forward to more from Mr. Deimel in the future, and will be interested in exploring some of his past works.