Sandokan

The native warrior race of Sandokan was locked in civil war for over three thousand stellar cycles, until one side created the Dark Heart. The living weapon went crazy and devastated life on Sandokan. Many years later, Sandokan's cities were in ruin, but there were areas of the planet where plant life either escaped the war, or has since recovered. Synthos, a scrap-monster with the Dark Heart at its core, attacked any visitors to Sandokan, continuing the spirit of hatred in which the Heart was created.

The Dark Heart of Sandokan
Synthos, powered by the Dark Heart, attacked the Autobot ship Star Arrow, bringing it down. This caught the attention of the Decepticons, who sent in Astrotrain to investigate the fate of the Autobot's Force Chip. On the surface of Sandokan, the Transformers encountered Synthos, who used Sandokan's ruined city landscape to attack the visitors. After a brief regrouping in one of Sandokan's foliage-covered valleys, Override and the crew of the Star Arrow succeeded in keeping her Force Chip out of the hands of both the Decepticons and Synthos. She removed the Decpticons from the site of the battle with Synthos, dropping them off on the far side of the continent. But despite Override's attempt to spare Synthos, the Decepticons managed to acquire the Dark Heart, likely stripping Sandokan of its sole sentient resident.

The AllSpark Almanac
Sandokan, which was inhabited by robots, was part of the Quintesson Pan Galactic Co-Prosperity Sphere.

Prime cartoon
During a battle on Sandokan, Wheeljack didn't leave Bulkhead behind. He later reminded Bulkhead of this fact while trying to defuse a bomb attached to his fellow Wrecker's chest.