To draw this back around, when I heard about the "rock alien" in High Republic my first thought was literally just "so, just ripping off the Horta from Star Trek, huh?" And I'm not even kidding, the Star Trek TOS novels had a reoccurring Horta Ensign (later Lieutenant) who was a shared character between multiple authors and so showed up in numerous Trek novels, including the most important Star Trek TOS novel series, the Rihannsu series.Thanks for the earworm Leslie.
"I may be the last on this planet.
The last of a great race’s dregs.
And if only you’d stop taking them for granite,
You’d see those big stone bowling balls are eggs!"
Seriously, meet Dahai Iohor Naraht. The original rock monster crewmember. And badass.
And it's not the only one to have shown up in the Trek novels and other Trek EU contents. Horta are one of the fandom's favorite aliens to have show up in stuff.
Compared to the Horta, Geode seems like a cheap knock off...