Sigma Star Saga for the GBA. Really creative mashup of an RPG and a side-scrolling shooter, with a cool weapon-configuration system thrown in. Definitely suffered a bit from platform limitations, but there’s absolutely more that could have been done with the core concept.
Shockingly good writing, too.
San Francisco had an emperor.
(He even “decreed” the construction of a bridge or tunnel between San Francisco and Oakland on the other side of the bay, predicting the existence of the Bay Bridge and Transbay Tube!)