Capstone

Extraterrestrials could be seen as gods if their powers dazzle us, but they’d differ from an immanent or transcendent God by being finite, physical beings within the universe, not its root. A hierarchy of beings—us, them, and beyond—fits both religious and speculative frameworks, potentially stretching from the mundane to the near-divine. Whether there’s an ultimate God atop it all, or just an endless progression of "higher" entities, depends on your worldview. What do you think—does the idea of a cosmic pecking order resonate with you, or do you lean toward a singular divine capstone?

Source: tatoeba (13312019)

“You see, I’ve never had a girl friend,” I added, by way of topping the obelisk of silliness with the capstone of fatuity.

Source: wiktionary

Success of the Apollo program has been the capstone to a series of significant accomplishments for the United States in space in a broad spectrum of manned and unmanned exploration missions and in the application of space techniques for the benefit of man.

Source: wiktionary

Capstoning a decade's worth of linked short stories, The Quiet War (2008) was a vivid and tense novel about a solar system sliding into conflict.

Source: wiktionary