In the mid 22nd century, Tholian starships were equipped with an energy-dampening weapon. In 2152, they disabled the Earth starship Enterprise with such weapons, rendering it completely powerless. (ENT: "Future Tense")
The weapon was encountered by Federation forces when the Breen entered the Dominion War as allies of the Dominion in 2375, at the Second Battle of Chin'toka. Since allied ships had never encountered the weapon before, it was especially effective against them. The weapon works by draining the energy of targeted ships, disabling their engines, weapons, and shields, thus making them easy targets for conventional weapons. Among the vessels lost to the weapon was the USS Defiant. (DS9: "The Changing Face of Evil") The Dominion had been in the process of retrofitting all Jem'Hadar vessels with the weapon. (DS9: "Tacking Into the Wind")
Klingon ships can easily be made immune to the weapon by modifying their tritium intermix. This was found by accident after the engineer of a bird-of-prey, the IKS Ki'tang, performed the procedure to correct a containment problem in the starship's warp core.
Unfortunately, Federation and Romulan ships cannot be as easily modified. However, this problem was solved when Kira Nerys captured a Jem'Hadar fighter with the weapon installed, allowing Allied engineers to study the dampening weapon in detail. (DS9: "When It Rains...", "Tacking Into the Wind") By the war's end, the Federation Alliance succeeded in developing a countermeasure to the Breen weapon, forcing the Dominion to discontinue its use. (DS9: "Extreme Measures", "The Dogs of War")