I'm running like five things at once aren't I.

Actually there's lots of bits and pieces to this story that I don't want to get tangled up yet, so they're all getting put into different places.
As mentioned in the Cataclysm's thread, the Liss are a race of ancient technologically advanced serpents, responsible for many many things. Possibly mankind, but who knows, Lissians are prone to mad schemes and suddenly falling off the radar!
This was also an experiment into making a fairly nice looking green scheme. I think it worked pretty well.
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Though the Lissians have never really had any need to protect themselves - their technology is more than enough of a ward against overconfident younger races - they have nevertheless concocted a number of technologically advanced warships with which to defend themselves. That's not to say they aren't capable of offensive action - the Lissian Salamander is a monster in battle - but others, like the Lissian Vanguard, are better suited to defensive actions.
Most Lissian vessels are based around the same core style with extra modifications as necessary for the design, technically allowing for ships to be retrofitted to an entire different class within a matter of hours, though this is a rare occurance. This flexibility is a noticeable trait in their ships, as well as the spawn of their creations-gone-rogue, the Cataclysm-class Motherships.
Salamander

The Salamander Mark Five is the cutting edge of Lissian Warship Technology. Three large engine and reactor assemblies provide power for the Salamander's Hellfire beam cannons, and it's primary Meson beam cannon. Like all Lissian ships, it mounts the tried and tested Microwarp Drive, which allows it to make instant, short and precise jumps in a sector. The drive recharges somewhat slowly, but it is incredibly precise.
Utilizing the latest in Lissian Armour Plating Tech, the Salamander's hull is astoundingly resilient for such a vessel, and six Subsector Shielding Generators provide temporary immunity to enemy fire for a section of the vessel. The Salamander mounts numerous Pulse Laser turrets and Flak Turrets for light offensive purposes, and also mounts a powerful Phase Beam Cannon. The PBC has 360 coverage but rotates very slowly, though it inflicts incredible amounts of damage when it does hit.
The Salamander is a very dangerous vessel to approach as it's pulse lasers are remarkably accurate, boasting a long firing range, and is also capable of deploying additional gun drone platforms to aid it's attacks with moderately powerful energy cannons. The Salamander shines at range, though it is also a proficient close-range combatant.
Lissian Vanguard

The Vanguard Mark Seven is one of the toughest ships in the Lissian armada. Whilst it is by no means the most powerful, it has four Lissian Barrier Generators, providing permanent near-invulnerability to the highlighted sections. The Vanguard is highly resistant to frontal and rear assault, but it's sides are weak, relatively speaking.
The Vanguard also mounts a Phase Torpedo Turret, making it highly effective against thickly armoured enemies.