Post
Testing your game idea with cardboard and dice before writing a single line of code.
Paper prototyping is building a rough physical version of your game -- cards, tokens, dice, hand-drawn boards -- to test core mechanics before investing in digital development. It sounds old-fashioned, but it's one of the most efficient design tools available. You can test and iterate on a paper prototype in hours rather than the weeks it takes to build a digital version. It forces you to focus on mechanics rather than getting distracted by art and animation. If a game isn't fun on paper, fancy graphics won't save it.
Example
The original prototype for what became Slay the Spire was a physical card game the developers played at their kitchen table. They iterated on card balance, deck-building mechanics, and encounter design entirely with physical cards before touching a computer. Sid Meier famously prototyped early Civilization concepts with board game components, testing the core 'one more turn' loop with physical pieces and handwritten rules.
Why it matters
Paper prototyping saves months of wasted development time by killing bad ideas early and cheaply. It also strips away the seduction of polish -- you can't hide bad design behind pretty particles when it's just index cards on a table. Every aspiring game designer should learn to prototype on paper before they open a game engine.
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