AFTERGLOW

The reactor went up at dawn, sixty kilometers northwest. The flash is over — now the fallout is drifting. Cross the contaminated valley and reach the Deep Shelter on the eastern hills before Day 20, when the airlock seals for good. Your enemy isn't a monster. It's physics. And physics can be outsmarted — but it will not be hurried past.

THE SCIENCE YOU'LL USE

• Amber stipple — iodine-131. 300 mSv if you bed down in it — but a half-life of 8 days: half of it vanishes on Day 8, half again on Day 16. Waiting works.
• Blue hatch — cesium-137. Only 100 mSv — but a 30-year half-life. It never decays. The fast highway is painted with it, and the detours cost full days.
• Grey wash — unsurveyed. Contamination there is unknown until you walk adjacent or scan it with a Geiger Counter.
• Buildings halve your dose, and you only absorb fallout in the square where your day ends. Sprint through hot ground; sleep in clean ground. Time · Distance · Shielding.

HOW TO PLAY

• Each day you hold 2 Action Points — two steps, or a step and a scavenge, or a step and a Geiger Check quiz. Only 1 AP once you're sickened. Forest, rubble and river cost a full day.
• Every step rolls the dice — hot dust, stray caches, twisted ankles, contaminated runoff, worse. A paper suit, a Geiger Counter, and knowing the physics are what stand between a bad step and a bad dose.
• The wind keeps working against you: every other day, fresh deposition lands downwind — ahead of you. The land does not wait for you to cross it.
• 500 mSv weakens you · 1,000 costs supplies daily · 2,000 starts a 4-day countdown · 4,000 is fatal.
• Rescue the four reported survivors (+10 each). Supplies kept +2 each, correct checks +3 each, and every 100 mSv costs you 1 point.