Combined military might of the universe

[Quertus]

The Earth Prime universe (Green Ronin) not only has time travel, it has superpowered Time Keepers and Guardians of Time to protect it's "proper" history from outside interference.

Having a force already in place to fight a proper time war is, of course, an advantage, of the same type as having a military already in place to fight a ground / air / space war; however, what exactly are these groups capabilities?

Second is the Book (from The God That Crawls). It is a spellbook that, once assembled, destroys all information other than itself. All. Information. Starting with other writing, ending with natural constants. The Monolith would allow a relatively safe and easy way to take its pages, one by one, to a target universe. Once assembled, it would make a potent weapon against them. Notably, nearly all sci-fi universes would be suspectible, because if they can't neutralize it near-instantly, all high-tech solutions for locating it are ruined. Sadly, the Book is destructible, though it renews itself (on the pages of other books, which must be recollected and reassembled).

Effects? Timeframe? Reasons sci-fi would be more vulnerable?