[Drakim]

Then maybe something more generic sounding like ClojEngine? Naming is hard lol. Core is fine, but maybe add one more word to it, because googling just "Core" to find your repo is difficult.

But I highly recommend changing the capitalization of Maker to maker to avoid being mixed up with the product RPG Maker. Adding "an" helps signal that it's a descriptor instead of a name too.

Core: An RPG maker and engine for Clojure.

[0xEF]

GamesCore - generic but serviceable name.

CrystalCore - because RPGs must have some sort of magic crystal, it's the law

CreataCore - why limit the name to RPG theme in case it develops into something larger?

Just a few quick name suggestions for OP.

[card_zero]

If it aspires to become like Unity you could maybe call it "Clunj".