Music for the Article
Mess with the timeline, Bad Things come after you.
Time flies like an arrow; fruit flies like a banana; Something like causality.
Time, like Death, hates being tampered with. Sometimes the determined chrono-criminal can find ways around these defenses, making general, grievous changes like altering a person completly.
In cases like these, time likes to get its hands dirty and ensure a less ironic and more graphic end to these revisionist historians with the help of These Bad Things.
These namless monsters are time's clean-up service. They eat and destroy people and things that directly threaten time with a Temporal Paradox. Like roaches, they "eat up" the crumbs and mistakes of time travelers, and if they directly make nuisances of themselves, eat them as well. Also like roaches, you can never kill them all, nor hope to survive against their mindless fury for long. At best, you can delay them, and hope to fix whatever it is you've messed up and marked you as FOOD.
The concepts of These Namless Monsters probably stems from the difficulty in representing the threat of creating a time paradox. It's hard to show that the whole of existence is about to slip down the timey-wimey plughole of fate, and that it's definitely bad. It's much easier for a writer to simply break out the Flying Time Monkeys to come and eat people.
When a paradox is triggered, they clean up the "wound" by erasing everything inside it.
When you've gone and broken time, all bets are off. More benign Time Crashes may take the form of a Groundhog Day Loop waiting for someone to find the magic key which breaks the cycle. In others, cause and effect itself may be shattered, resulting in a Fate Worse than Death for all affected, if not complete and utter destruction of the universe itself.
This is not about your usual temporal inconveniences, the kind that make your best friend vanish from the time line, put Fu Man Chu in the Oval Office or make medieval Japanese the lingua franca of the 21st century — that is, the sort that can be solved by a simple trip back in time to Set Right What Once Went Wrong. When Time Crashes it should have some large-scale, reality-breaking effects: holes get punched in the fabric of space-time, the Clock Roaches show up and start eating people, things that should happen one after another happen the other way around instead, or worse, simultaneously, etc.
This is not a simple thing to solve