Elegance in game design is the quality of generating rich, varied, and deep gameplay from a small set of simple, consistent rules. Go is the canonical example: two rule-types, 361 intersections, effectively infinite play space. Sellers identifies five properties of elegant systems — consistent rules, emergent behaviour, meaningful decisions, graceful scalability, and aesthetic pleasure in the system itself (Sellers 2018, see source-advanced-game-design).
Elegance is distinct from simplicity: a simple game may offer little; an elegant game offers much from little.
Related: systemic-depth-elegance, systemic-depth, emergence, second-order-design, game-balance