T3 zone, fourth authored graph. Shape: two stacked 3-way forks
(great_hall, upper_hall). The player picks twice in a row from a
wide menu — distinct from the binary forks in G8a/b and the parallel
Y-trees in G8c.
Completes lock-kind coverage by G8d: this is the first authored use of
LockLevelMin (tower_observatory gated at L7). With Perception (DC 14
study, DC 15 hidden_oratory), StatCheck INT (library), and LockNone,
all four non-trivial lock kinds now appear in shipping zones.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
