Mercury Gardens of Melanossus

The Mercury Gardens of Melanossus is the name of a garden planted around several large, naturally occurring mercury formations on the planet Nebulos. This unique garden is considered to be the planet's greatest natural wonder, and it has long attracted peace-loving Nebulans who enjoy meditating near the sparkling mercury.

Marvel Comics continuity
The Decepticons attacked the Mercury Gardens, attempting to take them over for unspecified reasons. A group of Autobots including the Monsterbots attempted to stop them, but failed to stand up to the Decepticon Headmasters and fled before their fighting did too much damage to the gardens. While it was a good plan, they don't seem to have thought it up fast enough; by the time the Decepticons celebrated their victory, the Mercury Gardens of Melanossus were mostly smoking craters.

As Lord Zarak saw that his war on Galen had caused the destruction of the priceless wonder, his resolve to defeat the Autobots faltered, if only briefly.