Concept: “The sewer guild has fled leaving these spaces to goblins and other chitter creatures, but they have left behind treasure and small stash of one of their key tools, Sewer Salve.”
Content: “a beard and skin care product that mixes the scents of patchouli, amber, and vetiver for a sweet earth aroma vaguely reminiscent of a urinal cake.”
Writing: I won’t spoil it, but there’s a pretty good pun on the lid.
Art/design: The most metal of yellow sewer grates.
Usability: A spreadable (edible?) urinal cake. I’ll get back to you once I get my hands on it. 

Concept: A collaborative monster-creation effort
Content: An undead, slimy, scythe-limbed swamp dweller
Writing: Mostly mechanical but still conveys character
Art/design: Exactly what you want your death-metal swamp monster to look like
Usability: In Twitter format

Concept: “As long as THE GATE remains active, all death is meaningless to the faithful.”
Content: Fairly straightforward dungeon with heretical overtones
Writing: An accessible mix of exposition and stat blocks
Art/design: Reserved use of color provides emphasis, aids navigation
Usability: Supported by explicit visual connection of text and locations 

Concept: “A darkly shimmering GROWTH has overtaken the town.”
Content: A pointcrawl amidst malicious overgrowth
Writing: Concise; mostly devoted to stats & mechanics
Art/design: Map and art are prominent without encroaching on the text
Usability: Small text emphasizes the visual elements but may be difficult to read

Concept: “From an underground Sarkash crypt, heretics and cultists terrorized settlers.”
Content: An occult dungeon with random events and escalating enemies
Writing: You may learn some new words; use them to terrify your players
Art/design: Establishes atmosphere; concreteness provides easy navigation
Usability: Very intuitive and efficient layout

Concept: “The world of people never much agreed with you; instead you sought the company of beasts” 
Content: A delusional zoologist.
Writing: A primitive class whose connection to animals is wildly open to interpretation.
Art/design: Cave illustration just adds further to the ambiguity to the story. 
Usability: Easy to use, flexible in characterization. Cover art by Nohr is available on Twitter.