Enigma is a ranged intelligence hero who is famed for two things: 1) being the most efficient jungler in the game. And 2) For having one of the most powerful teamfight abilities in the game, in the form of Black Hole.
Skills
Malefice is skilled second but maxed first.
Demonic Conversion is always skilled first but either maxed second (jungle & push mid-game focus) or last (teamfight focus)
Midnight Pulse is always skilled last but can be maxed second.
Black Hole is always skilled (levels 6, 11 and 16).
Items
Starting Items: Courier and/or Observer Wards (if no one else purchases), 3x Clarity, Sage's Mask.
Early Game: Soul Ring, Boots of Speed.
Core Items: Arcane Boots or Power Treads, Blink Dagger, Black King Bar.
Luxury Items: Refresher Orb, Aghanim's Scepter.
Situational & Utility Items: Mekanism, Drums of Endurance, Vladmir's Offering, Pipe of Insight, Heaven's Halberd, Shiva's Guard, Boots of Travel, Necronomicon, Scythe of Vyse, Ghost Scepter.