The Ultimate Antagonist

Manse Everard deduces that, in the Carthaginian timeline, the Scipios died at the Battle of Ticinus. Van Sarawak comments:

"'Somebody must have knocked them off...Some time traveler. It could only have been that.'" (Time Patrol, p. 219)

Everard replies:

"'Well, it seems probable, anyhow. We'll see.'" (ibid.)

Probable? When we read that, extra-temporal intervention was the only explanation that we knew of for a causality violation. And indeed the killing of the Scipios at Ticinus does turn out to have been the work of two Neldorian time criminals.

Therefore, it came as a total revelation when, three and a half decades later, Poul Anderson explained the untimely death of King Roger at the Battle of Rignano by writing:

"...no time traveler, no human blunder or madness or vaunting ambition brought this about. The fluctuation was in space-time-energy itself, a quantum leap, a senseless randomness." (The Shield Of Time, p. 344)

When I read that, I thought that it was an original concept, comparable to James Blish imagining the demons winning Armageddon. This is what Guion meant when he said that, beyond the tracking down of the last of the Exaltationist time criminals, there was:

"'...a larger meaning, a direction and an ending -'" (The Shield..., p. 8)

There is no longer any lone time criminal or gang of conspirators to track down. On the other hand, one individual's world-line intersects with so many others that small chance variations in his life affect the entire future. He is like the ultimate time criminal without even knowing it and Everard must indeed fight to the death with this personal causal nexus. Therefore, the ascending hierarchy of the Time Patrol's antagonists comprises:

individual time criminals;
Neldorians;
Exaltationists;
temporal chaos;
chaos channeled through the novel concept of a personal causal nexus.