A worthless toddler-sized souvenir cap from the floor's start that turns out to be a free ticket through the abyss portals.
The Train Conductor's Souvenir Hat is the junk reward every crawler gets the instant they arrive on The Iron Tangle — a blue-and-white toddler's cap reading "I rode the Iron Tangle," non-magical and immediately dismissed as garbage. Its secret is the floor's biggest twist: once Carl gains portal-sight and studies the Abyss, he finds the hat "marked" as one of only three items granting passage through the abyss gate. Simply equipping the stupid hat lets a rider ride a colored train to the end of the line and pass through to the early, stairwell-bearing stations — a revelation Carl broadcasts to every crawler on his network.
A cheap, non-magical blue-and-white toddler-sized conductor's cap embroidered with the words "I rode the Iron Tangle."
A worthless-seeming souvenir that is secretly the simplest key off the floor.
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