Prospero's Greater Vault
Named for the God of Wealth, Prospero's Greater Vault is an artefact that quadruples the rift capacity of its owner. It can be purchased from Merentesh, whose artefact shop is in Delos, as can its aptly-named cousin, Prospero's Lesser Vault.
A massive golden coffer, the Vault is adorned with a miniature spire and decorated with flowing carvings punctuated by fiery rubies. A door dominating the front of the safe is made of the same gold, and it bears a wheel-shaped, spinning handle that nearly spans the face of the vessel itself. Etched into the centre of the wheel is the Divine symbol of Prospero: a gleaming circlet.