Tell when the herds are at the river, including the stretch over new year

The elder says the herds come to the river from late autumn to early spring, and the check that should confirm it says they never come at all. Here is how to describe a stay that wraps around the end of the year and count how many days of it fall inside a journey or a quest.

Why this works

A season is a stretch of a circle, and a circle has no gap at its end. A stay that reaches past the last day of the year must count both its end and its beginning, or the rule says the herd never comes.

When not to use it

Skip it when migration follows weather or the player's own deeds instead of the calendar. There a fixed window will be wrong in some years; let the herd move when the conditions are met, and use this only for dates.

In the full entry

• What to build, step by step
• Starting values and the reason for each
• 3 common mistakes and the fix
• A diagram of every state
• 25 lines of example code with 4 checks that pass
• How your AI shows you that it works

Say this to your AI

Use the Spielerando entry "Tell when the herds are at the river, including the stretch over new year" (read_entry herds-that-migrate-across-the-new-year) in my game. Build it step by step, and show me how you checked that it works.

Or skip this and connect the MCP: your AI then finds all of this by itself.Connect the MCP