A so-called "hot Naptune" planet, Echidna rapidly orbits the star Typhon at a nose-to-nose distance much like a pegasid, or "hot Jupiter." Also, like the pegasids, it is believed to have formed further out and gradually migrated to its present position. Its core is higher in tock content than Sol's Neptune, the consequence of attracting asteroids and other debris as it journeyed through its solar system.
Mass Effect: Infiltrator·The Final Hours of Mass Effect 3·Galactic Codex: Essentials·Mass Effect Galaxy·Revelation·Ascension·Retribution·Redemption·Evolution
Soundtracks
Mass Effect Original Soundtrack·Mass Effect 2 Original Videogame Score [Atmospheric·Combat·Kasumi's Stolen Memory·Overlord·Lair of the Shadow Broker] ·Mass Effect 3 Original Videogame Score [Extended Cut·Citadel·Leviathan] ·Mass Effect: Andromeda - Original Soundtrack