Shinzon's huge Reman warship in Star Trek: Nemesis, armed with a thalaron radiation weapon and a cloak that let it fire while hidden.
The Scimitar was a massive warship built in secret by the Remans under Shinzon, the human clone of Jean-Luc Picard. It carried dozens of disruptor banks and torpedo launchers and had an advanced cloaking device that allowed it to fire while cloaked.
Its most dangerous weapon was a thalaron radiation generator, which could wipe out all life on a planet. Shinzon first used thalaron radiation to kill the Romulan Senate and seize power, and he planned to use the Scimitar against Earth. He also needed Picard's blood to survive the decay caused by his flawed cloning.
In the Bassen Rift, the Scimitar battled the Enterprise-E and two Romulan warbirds, badly damaging all of them. Picard rammed the Scimitar with the Enterprise, and Shinzon prepared to fire the thalaron weapon. Data crossed to the Scimitar, rescued Picard and destroyed the weapon with a phaser shot, giving his life as the ship exploded.