The Ash Wraiths appeared to be fiery creatures with bladed arms. They can become physical when they desire to but before then, any physical or energy-based attack against them is useless. Aside from their blades (which were easily able to cut through Kroton's armour), the Ash Wraiths were able to shoot beams of fiery energy as well as combine their energies to make a 'barrier' that could cover an entire planet.
They were shown to be intelligent - knowing how to speak and continuing the lie that they were the Archangels of the Odostra. Despite their power, however, the Ash Wraiths were vulnerable to the cold, as Izzy and Kroton were able to bring the majority of them down using a blizzard created from Paradost's weather controlling technology.
InformationEditAs part of the Master's plan to become the inheritor of the Glory and get his revenge on the Doctor, he enlisted the aid of the Ash Wraiths in his plan. When he wrote his fake holy book for the 'Church of the Glorious Dead' - known as the Odostra - he wrote in the Ash Wraiths as been the Glory's archangels. After Sato Katsura - an immortal samurai who the Master had tricked into his service - had conquered all of Earth (renaming the planet Dhakan) and Dhakan's technology had advanced enough, the people began to create warp-subtraction circuitry devices that were embedded into their chests.
The devices - known to the Dhakanians as 'soul keys' - were powered by the human body's internal combustion and, once activated, would temporarily open up a multidimensional portal. This would allow the Ash Wraiths to appear in the human's place, although the human who activated their key would be killed in the process (been led to believe they were becoming one of the 'archangels' themselves). Due to the Master planning to make every world like Dhakan once he became the inheritor, the Ash Wraiths seemingly stayed as his allies for this reason - believing that they would be on the 'winning side'.
The Ash Wraiths made their first true appearance to all when the Church of the Glorious Dead began their attack on the planet known as Paradost. The Ash Wraiths first attacked Kroton - who found that he could not harm the creatures but that they could harm him as one of them easily slashed through his armour with its bladed arm. Kroton fled to safety on the back of an expositor called Tyll (a large alien creature resembling a giant flying manta ray). Picking up the Doctor, Tyll flew at full speed but was still unable to escape the Ash Wraiths - with one of them killing Tyll while the others battled and easily defeated the Paradostrian militia sent to stop them.As the Church began their jihad after Sato had read the final page of the Odostra that the Master had deliberately hid away until the time was right, hundreds of Ash Wraiths appeared and (joined by a Dhakanian war fleet) began to destroy Paradost - attacking everything. Although the Doctor and Kroton escaped with the help of another expositor called Jynx (who they and the Doctor's companion Izzy had met earlier), the Ash Wraiths easily beat the Paradostrian militia as no physical or energy weapons worked on them. As the attack continued, more of the creatures formed an energy barrier around the planet to prevent the alliance of worlds from entering and destroying the Dhakanians. Although the Doctor came up with a plan to defeat them, he mysteriously vanished. In the three weeks that followed, Izzy and Kroton became fugitives on the planet, trying to survive with help from Jynx and moving through hyper-transit tunnels with refugees from all over Paradost as the combined force of the Dhakanian war fleet and the Ash Wraiths leveled entire cities to the group. Eventually, Izzy came up with a plan to stop them - which involved breaking into a base where an 'environmental impulse web' is located (which is used to control the weather). After Kroton deals with the Dhakanians outside and inside, Izzy and Jynx convince the scientists inside to brew up a blizzard - in the hopes it will bring down the Ash Wraiths and their energy barrier. Outside, Kroton is brought down temporarily by a trio of Ash Wraiths - but the blizzard started up. successfully starts to bring them down. In turn, the barrier the Ash Wraiths put up around Paradost breaks up and finally, the alliance of worlds manage to enter and begin to battle the Dhakanians. In order to prevent the process been reversed, Izzy and the scientists destroy the machinery. Although Izzy was captured by Sato Katsura, her plan had worked - with the Dhakanians been forced to flee Paradost and return to Dhakan with most of the Ash Wraiths having been caught in the blizzard while the remainder retreated. The Doctor (who had been taken to the Omniversal Spectrum by the being known as Esterath, before been taken to Dhakan) soon learned what the Ash Wraiths were from the Master - with the Master explaining that the creatures were psionic parasites that he found while exploring the Omniversal Spectrum. When the Doctor asks what the Ash Wraiths get out of been part of the Master's grand scheme, the Ash Wraiths simply reply that they get to be on the winning side - believing that the Doctor doesn't stand a chance against the Master.
When Kroton became the new inheritor of the Glory - the center of the Omniversal Spectrum - he used his newfound powers to heal the Doctor (who the Master had fatally injured in their battle), restore Earth back to normal, banish the Master and give Sato Katsura the honorable death he had always wanted. The Ash Wraiths were seemingly pulled back into the Omniversal Spectrum as a result of Kroton taking control.
Doctor Who: The Glorious Dead - Comics