(I'm french please excuse me for my english ) Hello there ! My sugestion is to add some fireflies in the game. They would be capturable by the player like the butterfly, but with the particularity of emitting some light. They can be put in a bottle and used to enlighten the room. Also the player can use them as light while he travels. For the distribution of the fireflies in the game, i think of a common species who emit just a bit of light but who would be grouped by tens near a area of water. But only at night . And some very rare species who emit more light and differents colors. The player would be interested by collect them and maybe use them for a craftable item who needs one of each color.