Just finished Thrawn Alliances - spoiler warning.
An enigmatic species known as the Grysk have observed the galaxy and its denizens since before the Clone Wars in preperation for a massive invasion.
Think Ssi Ssi Ruk 2.0 but with more emphasis on espionage and a shadow war.
http://starwars.wikia.com/wiki/Grysk
They have a navy with many ships of varied sizes including a class on par with a Star Destroyer.
They're perfect for a third faction in Armada...eventually.
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There are a few problems.
1) We don't know what their ships look like.
2) They've only just been introduced. Their story has yet to play out.
3) As of right now they're an exclusively book based antagonist (unless they feature in the Disney park which the book covers a bit.)
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I for one have always loved the idea of the malevolent oberserver race.
Alien ships would be a pretty cool counterpoint to the rebel and Imperial designs and give the designers some freedom.
Thoughts?
Edited by Forresto