The Destroyer is a massive Golem that has the ability to destroy the world using the 'Ring of Annihilation'. The Destroyer was said to be a legendary creature that would bring about a new age by destroying the world.
The Destroyer has the ability to form a wall of fire wherever he walks known as the 'Ring of Annihilation'. Once it has completed its journey, the massive Golem would spread the Belt of Fire across the surface of the world in a torrent of fire and ash and issue the world's destruction.
The Belt of Fire is possibly made by the dark magic of the Destroyer, that not even a Fire Guardian, such as Ignitus, could survive a second within its flames.
In The Legend of Spyro: Dawn of the Dragon, the Destroyer was resurrected by Malefor to bring about the end of the world, emerging from the volcano below Malefor's Lair. Malefor announced the resurrection to the citizens of Warfang the night of the Golem's defeat. As it spread the Belt of Fire across the surface of the world, Spyro and the others were having trouble keeping up with the monster. Determining that they would be unable to catch up to the Destroyer, the dragons along with their army set about ambushing it as it neared the end of its journey.
At the Dam, Spyro and Cynder opened the floodgates, flooding the canyon with thousands of gallons of water from the sea, which stalled the Destroyer. Once they had successfully stopped it, they flew in and attacked several key dark crystals on and inside its body. Unfortunately, even though the two had destroyed the creature's center crystal, this failed to stop the Destroyer, as Malefor controlled the Golem himself through some dark magic, and it reached the Belt of Fire to continue onwards. The Destroyer then completed its journey right as Spyro and Cynder confronted Malefor, breaking the world apart.
Role in the series
The Destroyer is a long defeated for in the series, cause Malefor desided not to use this monster again to avoid a repeat in history in the Legend of Spyro series..... At least, not until certain episodes in the cronitcles series.