In-world crafting mechanics --------------------------- Everything is crafted by the player (or crates/droppers/whatever) ejecting items into the world in proximity to one another, along with a noctis catalyst. The catalyst is, as all good catalysts are, not consumed in the crafting but simply facilitates the creation of the item in the world. If more than one thing can be created, one at a time is processed with at least 1 second between subsequent craftings. So if you drop 10x the ingredients for something and one catalyst down, it'll take 10 seconds to complete all the crafting, one per second. The catalyst has a custom entity to achieve that, extending EntityItem. One possibility is that you need to power up the catalyst somehow, perhaps leaving it in-world during the night. If that's the case, I should have it not despawn if left. or perhaps it should despawn after 5 minutes of daylight, but if it's night time it should not despawn. So you can leave it to charge overnight providing you have some daylight-sensor contraption to suck it into an inventory through the day. If we go with a charge/use mechanic then the catalyst can be used indoors to craft, but must be charged with sky access. (World.canBlockSeeTheSky, World.isDayTime, World.getCurrentMoonPhaseFactor, World.getCelestialAngle, World.isSurfaceWorld perhaps, although that might be mean, if the world has a sky vs. has no sky might be sufficient. Perhaps some rituals need to be performed away from the prying eyes of the moon and the stars?) With a charge mechanic, recipes could have a charge cost which will be subtracted from the catalyst. Also catalysts can't work together on crafting. Mechanics --------- All mod mechanics are based around night time. Early mechanics use white stained glass and black stained glass, using them in crafting recipes etc. Later mechanics involve stuff built from those beginnings. Early-game mechanics require single operations on or around dawn or dusk or midnight. Later mechanics require specific combinations of time of night and phase of moon. Some mechanics require multiple things to happen with time passing between them. Perhaps even tracking things like amount of time spent at night vs. in the day. Some mechanics require very exact timing, earlier mechanics let you build blocks to help you with that. Some kind of energy gathering in a block or item (the catalyst?) which gathers in the darkness and dissipates in the light perhaps. Perhaps two kinds of energy, one derived from the spaces between the stars and one derived from the moonlight. One associated with good things and one with bad. Some kind of sunset ritual (needs to be set up before sunrise, then lingers) which raises a soul from the land of the dead (green flash) A moonlight sensor (like a daylight sensor, but gives you feedback as to the amount of light coming from the moon -- sensitive to phase as well as time of day perhaps) night-dwelling creatures, passive so they don't contribute to the mob limit, some visible if the player is infused with moonlight, some with starspace. they can be captured by right-clicking them (they drop nothing and have only half a heart) for use in other mechanics Vanilla starting point ---------------------- To craft the light catalyst needs white stained glass and an ender pearl and you do that in a crafting grid. Crafting the dark catalyst needs in-world crafting though. White and black stained glass should act as the basis for moonlight and starspace gathering in blocks and items. In addition, mob drops associated with the night form part of the early game stuff. Spider eyes, rotten flesh, bones and gunpowder. Also sugar, redstone, carrots, In-game help ------------ A book, a feather, an ink sac and the light catalyst will produce the 'Spatio inter Stellarum' -- a book which details your research into the space between the stars. It's a little like a quest book in that it unlocks stuff as you go, but it's also not explicit about what happens, so it's kinda like a research tome too. A bit questy, a bit guidey, a bit record-y. The Stellarum looks like a book and appears to be enchanted. The tooltip (changes depending on the day/night cycle and the phase of the moon) suggests that it is somehow connected to some otherworldly power. In general, if viewed during the day, the words are comprehensible but the images fade/jumble/can't easily be understood. Possible effects ---------------- Early effects are potion construction. It's a "cheap" way to make low level simple potions which wouldn't require nether access apart from the wart/blazerod. So a water bottle, a glistering melon and the light catalyst can produce a potion of instant health (just the very basic one). Spatio inter Stellarum ---------------------- This book, like the thaumonomnicon, acts as a way to work out what you know how to do and what you can learn next. Rather than being nodes of connected data like the thaumonomnicon though it's a combination of a research journal with ideas, and an indexed record of what the player has discovered or theorised to work. Recipes may not be possible without the requisite knowledge which will be stored as world data for the player?