Alchemy: Rune Chain

You begin with four primal aspects — Air, Fire, Water and Earth — and a research tree where everything else is still sealed. Each research is a small hex board with two or three aspects fixed on it. Your task is to join them with an unbroken chain: two aspects link when one is a component of the other, or when both are components of the same thing. Lay the wrong neighbours side by side and nothing happens; find the route and a gold thread runs between them. The board hands you a counted stock, not the whole palette — enough for the route it was built around and a little slack. Spend it badly and you run dry, so scrape a node clean and take the aspect back. Every research you finish reveals one new aspect, opens the researches that needed it, and adds a page to the Library, where every aspect keeps its recipe and its known links. Twenty-two researches, twenty-six aspects, no timer and no failure state.