Applied the per-stage join to the other stage-resource fields. Of 338 distinct (field, value) pairs across the 22 stage objects, 31 are used by more than one stage. The strongest signal is CollisionMeshes: S24 CollisionSet_S11.bin SUBObjectiveSettings_S01 Anastasis Test S25 CollisionSet_S07.bin SUBObjectiveSettings_S07 Hargenteen Test S26 CollisionSet_S03.bin SUBObjectiveSettings_S06 Hargenteen Test S27 CollisionSet_S03.bin SUBObjectiveSettings_S03 Planet_Lebendorf Test S28 CollisionSet_S14.bin SUBObjectiveSettings_S01 Lebendorf EX5 S29 CollisionSet_S15.bin SUBObjectiveSettings_S15 Earth Test 6 of 6 challenge missions reuse a story stage's collision set. Control: S01-S16 are perfectly diagonal, CollisionSet_SNN <-> SUBObjectiveSettings_SNN, 16/16. Map, objectives and sky are borrowed independently - S24 flies S11's map with S01's objectives; S26 flies S03's map with S06's objectives under a Hargenteen sky belonging to neither; S28 flies S14's map with S01's objectives under S01's sky. Three of six mix, so "S24 is S11" would be wrong. S28 is the only stage with its own weapon table: 21 stages use EnumWeapon_Test.tbl (x132), the tutorials EnumWeapon_Tutorial.tbl (x36), and S28 alone EnumWeapon_EX5.tbl (x6). S28 was already the odd stage - the only rou_f004 flight - so this is a second hook on it. A datapoint for result-screens' open "what does EX_ mean": EX5 is also a variant suffix on real names - UN_f001_TCAF_DeltaSaber_T_EX5 and Weapon_TCAF_Ship_AAGun_EX5, 24 each. Not enough to fix the meaning. Method note: an unanchored EX[0-9] search over binary payloads returns EX0..EX9 at 100-180 hits each - pure noise from matching inside compressed data. Only prefix-anchored names are real. All fifteen artefacts byte-identical.