The forum entrance is part of the City of Senntisten quest line. It must be cleared before the rest of Senntisten can be entered. Once cleared, a barrier is uncovered.
Despite the Pontifex Maximus figurine (damaged) is listed in its survey interface, this artefact is never awarded as the hotspot isn't using the normal artefact discovery mechanisms. Instead, the figurine is obtained by interacting the pedestal once the entrance has been excavated.
Materials are only given for successful excavation attempts.
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