Two stages were not much of a ladder. Add STAGE 3 · 강철 회랑: 31 steel
cells the shells cannot pass, a double brick cap over the base and two
narrow funnels into it, 8 enemies with 4 on the field.
Getting to a later stage meant clearing the earlier ones. Read the stage
from the URL (#3 or ?stage=3) at load and on hashchange, so the shell's
nav chips and a plain link both land where they say. The stage buttons
and key hints are built from STAGES, so a new stage needs no UI edit.
Simulated 10 idle and 10 random-bot runs per stage: stage 3 leaves the
base standing in 6 of 10 idle runs, and its 144 reachable cells keep the
player out of a sealed pocket - an earlier layout had only 8.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>