Yep, as wordy said in his post, the chart if from the Official TV-Asahi (i.e. the network that airs the show) site for Kiva. Since they change the series every year, they try and come up with different themes for both the heroes and villains for each series. This year, with Kiva, they've chosen the chess theme for the "elite" Fangire. This is why they've collectively dubbed them "The Checkmate Four" and gave each member a chess-related name.