The Time Patrol's Most Deadly Adversary

(With the house to myself for a few days, I might get some more blogging done.)

The Nine, we think, changed history but the Danellians changed it back and founded the Time Patrol. This sentence implies at least three successive timelines:

history before the Nine had changed it;
history after the Nine had changed it;
the restored history, now protected by the Patrol.

The situation was probably much more complicated than that because the Nine were not the only time travelers involved:

"'...there had been uncountable opportunities for the foolish and the greedy and the mad to go back and turn history inside out.'" (Time Patrol, p. 11)

And also the sane, competent, well informed and well intentioned? But, in any case, these earliest time travelers, including the Nine, "'...were prevented from carrying out their schemes...'" (ibid.) by the Danellians and thus were not as such adversaries of the Patrol, which had not been founded yet. There is an entire pre-Time Patrol history of temporal changes.

Individual time criminals, like Stane and Castelar, tried to change history but were prevented by the Patrol. The Exaltationists made four such attempts but were prevented by the Patrol. Two Neldorians succeeded but the Patrol reversed their change. Lorenzo de Conti, without any access to a time machine, effortlessly and even unknowingly changed history twice and would probably have done so again if not killed by the Patrol. So he was their most deadly adversary.