Spatial Legacy
This "species lock" was something Gao Gong was extremely familiar with. Before the "player-exclusive canned food" (logout-disabled edition) was invented by advanced civilizations, this thing had long held the throne of the "Most Hated Civilization Weapon by Players." Almost every player loathed it to the bone.
Because of their "Fourth Calamity" nature, players actually didn't mind being dragged into major crises or disasters.
After all, a famous fisherman had once said, "The bigger the storm, the more expensive the fish."
Even "spacetime crises" and "spacetime disasters" that members of advanced civilizations greatly feared were things players happily plunged headfirst into.
This had even led to a method of exploiting timeline bugs. For example, one could travel into another timeline representing the past, frantically raise the favorability of some high-level NPC, then commit suicide to return to town—no, to return to the main universe—and enjoy the benefits of maxed-out favorability.
Because the same NPC across different timelines often shared favorability, and those important figures whom players could barely contact in the main universe might still be in a "baby Thanos" state in another timeline, making them extremely easy to manipulate. Raise their favorability, then return to the main universe and enjoy love-at-first-sight treatment. It was incredibly satisfying.
Naturally, the founder of this method was Gao Gong's original body. Using this technique, he had latched onto quite a few rich older women.
For players, there was no problem that "death" couldn't solve. If there was one, it was the "species lock."
In essence, it completely banned the evolution of an entire biological chain.
It did not target a single individual. It targeted a faction, or even an entire civilization's technology tree.
With that technology tree sealed, leveling up was impossible.
It was somewhat like the "sophon," except this was not