[M4-S1] Jenny rams you on the bridge and the creek turns #54

User story

As a player, I want a quiet creek to be broken by a car out of nowhere, so that the first scare lands.

Acceptance criteria

• Clean Rusty Creek after the landing: no enemies, nothing wrong
• Jenny crosses the bridge and rams the hero: cartoon knockback
• The region swaps to the rust maze and the hero restarts at its start (the crossing sequence, M3-S4)

Design and references

03 – Region 1 story beats · decision 24.

Dependencies

Suggested owner: Alexander (pipeline, art, scenes, deploy).

Verification

Play from landing to the maze start three times; the swap never shows a half-loaded frame.