Dark Willow is a ranged character. Her primary attribute is intelligence. The hero is mainly taken as a support. Most effective in the early and mid game.
Dark Willow is very efficeint in team fights. Her Bramble Maze ability holds enemies and restricts their movement, Cursed Crown stuns multiple enemies at once or forces opponents to change their positions, the Terrorize ability takes away enemy's offensive advantage, and Bedlam deals a huge amount of damage to a single target unit, which usually forces enemies to share damage. The Shadow Realm ability allows the hero to avoid most of the target abilities and deal a lot of magic damage to an enemy. This ability can be upgraded with Aghanim's Scepter, which will allow Dark Willow to become another core.
Mireska grew up in Revtel, a cutthroat nation where manipulation and murder were the norm. She was quite adept at navigating the unspoken laws but she found the whole thing rather boring. So, Mireska did what most rebellious children do: burn down her family estate and set off with her pet wisp Jex to live the life of a wandering grifter.