It is amazing how different the same textures and 3D models can look depending on how the scene is lit. Lighting can be used in game design to guide the player to the goal, to signal danger, and to hide enemies so they attack out of shadows.
Setting a light and changing its color and intensity is easy. However, to keep a mobile game from lagging, lights are like salt added to a meal. Too much and it becomes inedible (or in a game unplayable).
A design goal of Ratkey has been to motivate the player by showing glimpses of lower levels level from the current plane they are playing on. This also makes the current level more interesting by giving a sense of height and depth beyond the current walls.
Lanterns and torches are have been key elements as they give a bright focus for the scene and reason for why there is light there. Both the lanterns and torches are excellently crafted 3D models and are interesting to view close-up. As a result, they serve multiple points of interest to the player from a variety of distances. The player’s curiosity is satisfied as they get closer to lantern and torches.