Subnautica clone Astrometica is the most flagrant rip-off I've played in a year that also contains Palworld
Astrometica is Subnautica in space and to developer BeryMery's credit, the game makes zero effort to hide this. It's right there in the dog Latin of the title. It's got Subnautica's premise of being a shipwreck survivor starting afresh from an escape capsule, piecing together the backstory signal by signal, database entry by database entry. It's got Subnautica's core loop of exploring while dealing with the problem of decreasing oxygen, scavenging fist-sized chunks of raw material and scanning wreckage for blueprints, then crafting items and gear back at base.