Forced-matter shell

A forced-matter shell was a huge, artificial shell that could be created by the Time Lords to "cover up" a breach in the space-time continuum.

After winning their war against the Great Vampires, the Great Houses of the Time Lords covered up the breaches between their universe and the Spiral Yssgaroth using "forced-matter shells" disguised as ordinary planets, a project overseen by Rassilon himself. (PROSE: Interference, The Book of the War) According to a dramatised version of ancient Gallifreyan history shown to Sam Jones by Faction Paradox, one of these artificial planets was Earth. This meant that drilling into the Earth's core would risk reopening the breach and allowing the Yssgaroth to leak back into the universe, (PROSE: Interference) matching the way Stahlman's ooze mutated humans into monstrous, primal creatures (TV: Inferno) fitting the description of the Mal'akh. (PROSE: The Book of the War) The breaches existed over node points in the meta-structre of history, matching Earth's pivotal point in the history of the Spiral Politic, which The Book of the War claimed did not actually derive from any special quality on the part of humanity itself. (PROSE: The Book of the War)