The NSEA Protector is an Epic Grade 4 Explorer available from level 40, built to fight Sarris and his forces while doubling as a strong all-around ship thanks to a genuinely useful support ability. Its name comes from the (in-universe fictional) National Space Exploration Administration. With high impulse and warp speed, it's also the fastest way to cover ground once you're operating in the Mirror Universe.
Bringing the Protector into the Mirror Universe grants increased damage against MU hostiles and a boost to raw Trellium mining, and it's the only ship capable of reaching 15 new MU systems without being destroyed by a lethal minefield hazard -- alongside a whole new Mirror Research expansion. Those new areas add Omega Mirror Universe Hostiles, which drop a new raw Omega Trellium variant. Refining raw Omega Trellium yields Liquid Omega Trellium and Omega Mirror Dust (both on a 22-hour cooldown), and Omega Mirror Dust is the only way to unlock the new Mirror Research nodes -- covering Rift Key travel cost reduction, a critical damage floor, Isolytic damage for FKR ships, cost efficiencies for research materials (including Sigma), the War Room and Artifact Gallery, ship upgrade/scrap speed, an Apex Barrier in PvP, and opponent critical-damage reduction.
The Protector's signature ability, Omega-13, rewinds time just before a fatal blow lands, letting your ship survive combat it would otherwise have lost -- the effect can trigger for any ship in the vicinity, friend or foe, and consumes Omega-13 Matter to fire. Refits and research can further raise the hull-health threshold at which it kicks in.