Star Trek: 10 Most Powerful Ships
5. D'deridex Class Romulan Warbird
The Romulans are possibly the coldest, most calculating and least trusting species in the Alpha Quadrant. They look similar to Vulcans, except they're more dominated by paranoia and a desire to rule the galaxy than their cousins. That's probably why they developed a ship like the Warbird.
Like the Klingons, the Romulans have been around since The Original Series. After a 53 year hiatus from the affairs of the Alpha Quadrant, the Romulans reappeared on The Next Generation when a Warbird decloaked in front of the Enterprise-D. It was a disconcerting moment for all involved as no one knew what the Romulans wanted or how powerful their ships were.
D'deridex Warbirds are as dangerous a ship as you're going to find in Star Trek. They are large, powerful and heavily armed. On top of that, every Romulan ship is equipped with a cloaking device, meaning this beast can appear out of nowhere and open fire. But they prefer subterfuge to open combat, so they're more likely to stay cloaked and watch what's going on.