It seems you're a below-average trumpeter who has been unfortunate enough to incur the wrath of your obnoxious (and astonishingly stupid) king, and the game opens with you being tossed into a pit. As with everything else in Augmented Fourth, however, even this unusual premise is crafted in ways you might not expect: you spend five moves simply falling into the pit, trying to grab onto things as you fall (and failing), and listening to the banter of a couple of nasty guards whose stupidity rivals the king's. Lest you think that all this heralds a conventional hero-struggles-against-injustice story, the author plays virtually everything in this scene for laughs, such as the guard's reading of your sentence: "This I hereby put to paper as my word is the law when the law is my word, when it is heard. Indeed. Thus I spake. Er, spoke. Alright, scribe, stop your dictating now." You eventually find an abandoned underground settlement of sorts, and meet one of its denizens, and the story that follows is consistently and entertainingly whimsical.
Humor in IF is difficult to do well, since the author has so little control over how the player approaches the story, and the lack of control over the course of the story often means that the timing of your otherwise hilarious jokes may be ruined by no fault of your own. (And things like funny room descriptions aren't enough, since few descriptions are funny on the hundredth reading.) Accordingly, the best humorous IF relies on absurdity and fourth-wall humor rather than jokes as such, and Augmented Fourth fits that category: the funniest bits rely on the reliable trope of the Ridiculously Stupid Adversary, and the world you end up discovering is replete with cartoonish humor. The humor, in other words, has technically been done before, and yet it works: this author has an unerring ear for comic style, whether in the form of simple absurdity or barbed IF reference. (From the opening scene, when you're in the pit: one of the guards shouts, "It must get pretty tedious explorin' a room with no exits in any of the four cardinal directions but it wouldn't be much of a prison otherwise, eh?") The development of the plot, while competent, isn't quite as good as the writing; once you get past the intro and reach the main body of the game, you're essentially given a lot of puzzles to solve and an eventual goal to attain, and while it's a safe bet for experienced IF players that solving the puzzles will lead to reaching the goal, there's nothing to make the connection as such. To be sure, Augmented Fourth has a lot of company in that respect--not many games really integrate plot and puzzles more thoroughly than giving you an overall objective and perhaps an initial nudge--but it's still worth noting for those who crave a real melding of the narrative and the crossword. On the other hand, there's plenty of story that underlies the puzzles--i.e., the solutions to most of the puzzles rely at least in part on information specific to the game, so you won't get far without taking the time to read and understand the backstory. That reduces the sense that the game was an excuse for the puzzles, since the puzzles are specific to that game and wouldn't make sense in any other context. In short, while the progress of the plot isn't really related to the puzzles, the details of the story are, which certainly beats total independence of the two elements. Augmented Fourth does incorporate a device to reduce the sense that you've left the domain of plot and entered the realm of puzzles: periodically (in fact, at key points after you solve certain puzzles), you're shown cut scenes featuring the obnoxious king. The scenes are significant in several respects: they explain the premise of the game and give a basis for several important aspects of the setting, they develop the king's character (always worth a laugh), and they give your quest some context. To explain in detail would spoil the game, but suffice it to say that the cut-scenes turn your overall objective from saving your own skin to something more generally beneficial. It doesn't affect the puzzle-solving, but it does make the game feel more fleshed out. It's worth noting because, as most IFers know, giving a PC a set of motivations that explain every puzzle isn't easy; the cut-scene approach, which gives the PC's actions a temporal context (i.e., "meanwhile.") and, to some extent, an apparent link to other things that are going on. Technically, I suppose, it's not a perfect substitute, but it does create the illusion of involvement in the plot (as opposed to solving unrelated puzzles). At any rate, even if you don't buy the illusion, the cut-scenes are hilarious, which is a more than adequate justification for their presence.
The puzzles themselves are creative, on the whole, and they revive something akin to Infocom's spellcasting system, with a few inventive (and amusing) twists. Chief among the benefits of this is the possibility of trying out your spells on various objects in various contexts, with accompanying potential for humor, and I'm pleased to report that the author left very few stones unturned in that respect. Moreover, not all the puzzles depend on the spells (nor do they apply the spells in straightforward ways), so solving puzzles isn't simply a matter of leafing through the spells to figure out which one applies, which sometimes happened in the Enchanter series. Some of the puzzles involve rather obscure intuitive leaps, and one relies on information that an NPC provides only randomly (meaning that you may not hear the relevant bit unless you wait around for a while), but on the whole they're both challenging and reasonably fair (and the author has uploaded a walkthrough to GMD). It's also nearly impossible to make the game unwinnable (though there are plenty of deaths)--the game goes out of its way to replenish finite resources and provide multiple opportunities to solve puzzles.
Augmented Fourth doesn't transcend the limitations of the form or subvert the player's expectations in any fundamental way. Still, it's one of the best-written and best-programmed efforts to be released this year, and it's a good example of what you get when an author really goes overboard in providing funny responses for obscure actions and filling out the backstory. It's a polished, intelligent work that deserves your attention.