The Dawn - 113:3
From the evil of darkness when it descends.
In the context of verses 1, 2...5; for protection from Satan:
Explained in Detail/41:36
If any thought from Satan takes hold of you, seek refuge in Allah. He is All-Hearing, All-Knowing
The Believers/23:97
"And say, "My Lord, I seek refuge in You from the whispers of the devils."
The Believers/23:98
I seek refuge in you, my Lord, from their presence near me.
The Family Of Imran/3:36
"When she gave birth to her, she said: "My Lord, I have given birth to a girl."Allah knew what she would give birth to. I have named her Maryam, and I beseech you to protect her and her progeny from Satan, the exorcist."
The Cow/2:257
Allah is the sovereign and the friend of those who believe; He brings them out of darkness into light. But the friends of those who disbelieve are fierce men; they bring them out of light into darkness. They are the people of the Fire, they will abide therein forever.
The Heights/7:200
Whenever an evil thought from Satan enters your mind, seek refuge in Allah; He is All-Hearing, All-Knowing.
The Heights/7:201
Whenever a dark suggestion from the devil reaches the righteous, they immediately remember. So they immediately see.
The Dawn/113:1
"Say, "I seek refuge in the Lord of the dawn."
The Dawn/113:2
From the evil of what He has created.
The Dawn/113:3
From the evil of darkness when it descends.