subturns

A subturn is a subdivision of a single turn in a turn-based system, used to model finer-grained actions, reactions, or phases within what is nominally one player or entity turn. The concept appears in board games, tabletop role‑playing games, computer and video games, wargames, and simulations where designers require finer temporal resolution than whole turns allow.

Purpose and usage: Subturns increase accuracy of time representation, enable interrupt and reaction mechanics, and support simultaneous or interleaved actions without abandoning a turn-based framework. Common implementations include phased sequences (movement phase, attack phase), alternating microturns between players, action points allocated across multiple subturns, and reactive interrupts that occur in response to specific triggers.

Design considerations: Subturn systems trade simplicity for precision. They can improve tactical depth and fairness but may add bookkeeping, slow gameplay, and complicate rule design. Balancing visibility (what players know about upcoming subturns) and responsiveness is a common challenge.

Variants and terminology: Related concepts include phases, microturns, ticks, and WEGO/IGO/IGO-UGO systems; the exact meaning of "subturn" varies by context. Outside games, analogous subdivisions appear in simulations and control systems where discrete time steps model continuous processes.

Etymology: The term is a straightforward compound of the prefix sub- and turn, indicating a smaller unit within a standard turn.