6) Krenim Time Ship, Star Trek: Voyager (“The Year of Hell”)
In her seven-year journey across the Delta Quadrant, the starship Voyager managed to do one thing really, really well, and that was piss people off. In fact, more often than other Star Trek series did first contact situations end up with someone shooting at the Voyager. You would think that between Species 8472, the Kazon, the Borg, Hirogen, or countless other hostiles encountered, someone would be able to successfully cap Voyager’s ass, but it was the Krenim that came the closest. The Krenim, now acting all Billy bad-ass, decided that they don’t want Voyager to exist either, and hit out by firing their wibbly-wobbly timey-whimey gun at them, starting what became to be known as the Year of Hell. Of course, temporal mechanics being what they are, eventually the Krenim time vessel removes itself from time. Therefore removing all of the damage it did from time, and all is right with the world again, or as best as we understand it.
5) Scimitar, Star Trek: Nemesis
The Scimitar was born and bred for war, armed with a whopping 52 disruptor banks and 27 photon torpedo tubes, over five times the normal armament for a battle-ready starship. She had what was considered a flawless cloaking device that gave off no emissions that could be used to track her. The only way to find her was to fire blindly until a weapon struck her shields. Speaking of shielding, she was also equipped with the second set of shields, making her almost impenetrable. She had an obviously impressive power generation system, as she was faster than the Enterprise-E, even while cloaked, and could decloak specific sections of the ship to fire specific weapons. As if that wasn’t enough, she was also a carrier, holding dozens of Scorpion Attack fighters.
But wait, there’s more! As if the Scimitar wasn’t powerful enough, she was also equipped with a Thalaron Radiation weapon that once powered up and charged for seven minutes, could deploy against a planet and turn its inhabitants into dust. Two Romulan Warbirds and the Enterprise could barely put a dent in her, and it took the Enterprise literally crashing into her to do any significant damage.