Jemini ("Jemini Block") is a logic puzzle invented by Naoki Inaba (Japan). A rectangular or square grid contains letters in some cells. The goal is to divide the grid into regions such that each region contains exactly one letter. In regions of the same size, shape and orientation the same letter must be exactly at the same position.
Cross+A can solve puzzles from 3 x 3 to 30 x 30.