Zarude was a species of Pokemon that was extremely hostile toward humans.
This was true both in the Pokemon anime and its background settings, as well as in Mark's world.
Only in a very small number of Parallel Time-Spaces, where Mark had been raised by Zarude, had he become a bridge of communication between Zarude and humans.
Other than that, Zarude rarely showed themselves before humans. If humans invaded Zarude's Chaos Space, the entire Zarude clan would attack them together.
However, perhaps because Mark had become an immortal, this group of Zarude did not regard him with hostility.
Not only that, these Zarude agreed to Mark's request. They said they could make contact with the humans of Clear Stream Gym and could even send some Zarude to Clear Stream Town.
Among the Zarude who would be going to Clear Stream Town was the "Father" who had become Mark's father in a few Parallel Time-Spaces.
But something was still missing. After interacting with him for a while, Mark gave up and did not deliberately seek further contact with "Father."
Some things, once missed, were simply missed.
In the end, Mark gave up on catching Zarude.
Still, even without Zarude joining him, Mark's Pokemon lineup gained two more members.
The first was Lugia.
Although Lugia had been controlled by Corey with the Mind Control Device for several years, he had never become Corey's Pokemon.
After spending some time with Jirachi, Mew, Rayquaza, and the other Pokemon, and after seeing Mark, Lugia decided to join them. Mark then caught Lugia.
The other Pokemon was Necrozma.
Unlike Lugia, although he had likewise been controlled and interfered with by a machine, Necrozma had already acknowledged Corey as his Trainer, and a certain bond had formed between them.
However, the Necrozma Mark caught was not Corey's