I am a beginner to Unity3D and 3D game development in general. However I would like to implement a simple grid based game (similar to chess). What is the right way to do this? What if the map is not flat and if some grid cells have different heights? What if the entire map is not square like a chess board, but rather an irregular shape? Would it be better to use an external 3D modelling software to create the map or would it be better to just use Unity3D's own terrain? How would I ensure that the grid is always visible to the players since I am not interested in colouring each grid square black and white.