The Cataclysm

The Cataclysm was the first battle of the War in Heaven. It was fought on Dronid.

It was thought by most War-time powers to be the incident which killed the Doctor, but – as Qixotl knew – that was not entirely true. (PROSE: Alien Bodies)

Buildup
After the fall of the renegade Presidency, Dronid was littered with leftover time-technology. As a result, it became the centre of the Spiral Underworld, with criminal organisations from across the lesser species flocking there to gather time technology. This became the first front for the enemy, who not only began gaining power, but also spread its deep-rooted philosophy. Not only did it gather support from other criminal organisations, the groups that tried to subdue its rising power did so by learning its methods and inadvertently spreading its philosophy.

Upon realising this, the Houses tried and failed to retro-alter Dronid's timeline, but discovered it had been protected by the enemy. Instead, they tried to build their own powerbase on Dronid by planted an agent on Dronid to counter the enemy infiltration by subverting and controlling Faction Paradox's presence on the planet. However, this agent "went native", and the Houses gained little ground against their opponent.

With it now obvious that the battle would need to be fought on the ground, the Houses and their enemy began to aggressively ally themselves with other off-world groups. The enemy supplied its affiliates with greater and greater levels of time technology, but the Houses responded by coopting larger and larger military units, (PROSE: The Book of the War) including the Gabrielidean military. (PROSE: Alien Bodies)

The first 90-form timeships probed the perimeter of Dronid's noosphere days before the battle began. (PROSE: The Book of the War)

Eruption
Two days before the Cataclysm, the Doctor, (PROSE: Alien Bodies) a particularly interventionist diplomat from the Great Houses, attempted to make peace on Dronid, claiming that he had an old connection with one of the enemy's agents there. However, his acquaintance betrayed him, and he was thought to have died as the battle began.

The allies of the Houses began the first battle by moving their warships into position around Dronid and bombarding the enemy powerbases there. The enemy had been prepared for this, but the bombardment activated the world processor engines that House Dvora had installed into the planet's foundation after disposing of the renegade Presidency. Locals were forced to take shelter in bunkers as a poisonous sky blew lethal, all-consuming clouds of spores through the streets.

Compassion may have been involved in the battle on Dronid. (PROSE: The Book of the War)

Aftermath
Even fifty years after the Cataclysm, Dronid was still suffering the effects. Cults and criminal groups were the only government left. (PROSE: Alien Bodies, The Book of the War)

The Faction Paradox mission in Smithmanstown owned one of the few automobiles to survive, but its bodywork had been eaten away by the Time Lords' clockwork bacteria.

The Doctor corpse was planted in the ruins of Dronid to make it appear that he had died during the battle. (PROSE: Alien Bodies)