This little guy is a Pleiospilos nelii, also known as a Split Rock succulent. These guys are a lovely green and the pots of brimming with lots of little succulent plants for your to care for. They comes from South African and grow in the desert. Keep this in mind when caring for your little plant.
This succulent doesn't like damp soil, so too much water can easily kill it.
They love sun so make sure they are in a south-facing window
Slow growers, they can stay in the same pot for years to come.