While entirely within Dim Light or Darkness, you can use a Bonus Action to teleport up to 60 feet to an unoccupied space you can see that is also in Dim Light or Darkness. You then have Advantage on the next melee attack you make before the end of the current turn.
Shadow Step
Raw data
{
"name": "Shadow Step",
"page": 105,
"level": 6,
"__prop": "subclassFeature",
"header": 2,
"source": "XPHB",
"entries": [
"While entirely within {@variantrule Dim Light|XPHB} or {@variantrule Darkness|XPHB}, you can use a {@variantrule Bonus Action|XPHB} to teleport up to 60 feet to an unoccupied space you can see that is also in {@variantrule Dim Light|XPHB} or {@variantrule Darkness|XPHB}. You then have {@variantrule Advantage|XPHB} on the next melee attack you make before the end of the current turn."
],
"className": "Monk",
"classSource": "XPHB",
"subclassSource": "XPHB",
"subclassShortName": "Shadow"
}