When immersed in a shadow, a darkling may opt to use their action to become invisible while within the limits of the shadow. The invisibility adds an effective +2 AC as it is harder to hit something that you can't see. The invisibility is removed when it is hit or when it leaves the shadow.

A darkling may see in total darkness for as far as it can see.

A darkling may choose to create a sphere of darkness in a radius of 10 times its level. All darkvision can pierce this cloak of darkness. This DOES NOT grant any abilities to the darkling as the darkness is artificial. However, it does remove the disadvantages of being in the light.

When a darkling is in light, it has trouble seeing and has disadvantage on Perception. A darkling in light also has -1 to all Strength related checks and saves.

The weight of a darkling allows for quicker and sharper movement. +2 to Dexterity.

A darkling can commit the painful act of splitting in 2 with 1 half retaining the consciousness of the darkling. It will take 1d6 damage, but will dodge the attack. 

A darkling in darkness becomes a little stronger overall.

A darkling in a shadow can change that shadow into the shadow of anything it sees. It cannot turn the shadow invisible.

A darkling can shift into a pre-determined forms.