Wanted: Monty Mole (1984), which begins the series with Monty traveling around a coal mine collecting pieces of coal and other miscellaneous objects whilst avoiding various nasties and the infamous crushers. The game was created in response to the British Miners' Strikes and saw the lead character collecting coal in order to keep his family warm.
Monty is Innocent (1985). In this game, Monty has been sentenced to five years in Scudmore Prison for stealing a bucket of coal. Monty's best friend, the mysterious masked rodent, Sam Stoat, is determined to set Monty free.