Ether

Ether is a Jupiter Djinni found in Golden Sun: The Lost Age, and is numerically the tenth Jupiter Djinni and is therefore the third Jupiter Djinni introduced in The Lost Age.

Location
It is found in the town of Garoh, accessible after you've acquired the Reveal Psynergy from Air's Rock.

Description
When Set, it increases base HP by 8, base PP by 4, base Agility by 3, and base Luck by 2.

When used, Ether restores a target Adept's PP meter by 30% of his or her total PP meter.

Analysis
Ether is incredibly useful as it is one of the few things that can restore an adepts PP meter, and being a djinni it can be used multiple times.