FEMACUBE³ is one of the game’s Factions.
It was partially the theme of the NFT project’s second release DROP02 - Bum Legion 2099 & F.E.M.A.C.U.B.E.3 So far all cards belonging to the FEMACUBE³ faction were released in that set.
Spellings
There are various stylistic ways of depicting this faction’s name, including as a dotted acronym, or with a superscript 3 for the cubed indicator.
All these variations refer to the same thing, so they’re used interchangeably depending on space limitations and such.