Robot City is a world created by the LUP Team Deerbite. It was one of four new worlds that debuted at BrickCon 2010. The enemies are corrupted robot citizens. It was released on the 23rd of February, 2011. It uses many assets originally designed for Nimbus Park, such as bushes and plants, and the Robot Mower.
The robots refer to minifigures as "Organics", despite their being plastic.
The names of the quest giving robots are based on an ascending power of two, which is also the base of binary counting. Unit 16 is 2^4, Unit 32 is 2^5, and Unit 64 is 2^6.
LEGO Universe - Robot City Prototypes More (Team Deerbite Maps)
Robot City test maps
The physical prototype version of Robot City built by the LUPs who designed it.