Mario & Luigi series
The coins appear throughout the world. Many coins are hidden inside of Question Blocks. Mario and Luigi will also be rewarded with them after defeating various enemies and bosses. As the game progresses, these Coins tend to replace the normal coins as the main rewards.
Paper Mario: Sticker Star
Just like the Mario and Luigi series, the coins are scattereed around the world. While some are located in Question Blocks, many are found lying on the ground. In World 4, there are few singular coins, and there are many more larger coin rewards. These are also rewarded for defeating some standard enemies.