The four original types of marshmallows in Lucky Charms cereal were: pink hearts, yellow moons, orange stars, and green clovers.
Blue diamonds were added in 1975. (That’s the year I was born, so I don’t remember that.) Purple horseshoes were added in 1984. (I do remember that.)
After that I kinda moved on to cereals that don’t actively try to kill you, but apparently red balloons were added in 1989, rainbows in 1992, pots of gold in 1994, leprechaun hats in 1996, and shooting stars in 1998.