Ibb and Obb

ibb and obb is a puzzle platform video game developed by Sparpweed Games for PlayStation 3 and Microsoft Windows. It began as Richard Boeser's graduation project and debuted at IndieCade in 2008.[1] The green creature, ibb, and the pink creature, obb, travel through a world divided by a thin horizon line; on either side of the barrier, everything is inverted and gravity works in opposite directions.[2] The game is focused on cooperative play and the two characters must work closely together to progress through the game.[3] The intentionally lowercase names of ibb and obb come from the book The Well of Lost Plots by Jasper Fforde, where two "generics" with these names must earn their capital letters by evolving as characters.[4]