What will the initial set of Generation 10 core series Pokemon games be named after? (Not including expansions, remakes, spinoffs, interquel ("Legends" games), etc.)

In case of ambiguity between whether the name refers to something or a color named after it, this will resolve to the thing itself, not the color. Regarding the natural/artificial object options: "Artificial" and "natural" refer to whether the object was human-created; these categories also exclude anything that overlaps with one of the other categories. "A period of time" can be either a single, recurring, or generic span of time, eg morning, evening, day, night, past, future, minute, hour, summer, winter, etc.

This question will resolve when the game titles are announced.