Nerds Dark Willow
Dark Willow is an intelligence hero, who provides a lot of disables in fights and hard to bully out of lane. She has a great escape/zoning tool, as well as a lot of ways to setup kills, deal massive amounts of magic damage and provide utility in temfights.
Skill Build Timeline
It's incredibly strong ability, but we don't really need to max it early on: value point is enough. You main combo should be E+Q+charge W and attack with Bedlam.
Our surviveability and zoning tool. Charge it until exclamation mark appears and attack enemies.
Mobility and mana, additional save as well as setup for your Q or E (use E, wait for around 1.5 seconds, use eul).
You will have mana issues early, while also wanting to get Greaves, so Arcane boots seems like most optimal choice.
You're pretty slow hero anyway, so early Wind Lace will be really helpful. You can use it while upgrading Urn as well.