Finding Egon
Travel from Castigor's Keep Beacon to the tower southwest of it. Egon is a named NPC exchange, not a normal merchant inventory or Shell unlock.
Keep Egon separate from Vellen, who belongs to a different Mammon route. The name and location matter because the two are easy to mix up in a route note.
The Gloom offering
The documented transaction is a 10,000-Gloom offering followed by a doubled return. Treat it as one named exchange rather than a general Gloom rate.
Do not commit currency you need for a Shell or weapon upgrade until the tower interaction is available on your own save.
What is still unknown
Repeatability, alternate rewards, and patch-specific conditions are not established. A single doubling event is different from an unlimited currency loop.
If the tower route is blocked, check nearby progression and Beacon state first. A bypass, required quest order, or guaranteed workaround is not established.
Related videos
Watch the route and combat use
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