Unbefallen is a collective alternate-history experience and research project developing UNB, an in-house forecasting model. Its approach explores how people make decisions in imagined histories where a real historical event took a different turn, then uses that study to support probabilistic forecasts of real-world events. Rather than scripting an alternate history in advance, Unbefallen invites players to shape a shared world through their choices.

Participants join one of four factions—Authority, Coordination, Conviction or Mobilization—and consider events from that group’s perspective. They discuss situations, propose actions and vote, with each player’s vote counting equally. An engine advances the world based on the factions’ decisions, while a chronicle records the resulting events and consequences.

These interactive experiences are intended both as a shared activity and as material for UNB’s research and development. The project aims to assess forecasts against observed real-world outcomes, not fictional histories alone. UNB 0.

1 is in development, and its forecasting performance has not yet been validated