Nocturne

Strengths

Using Paranoia at a critical moment is well worth it even if you cannot use the dash.
Duskbringer isn't only an offensive ability. It can be used to close distance out of combat or escape from certain death.
Use Shroud of Darkness in tandem with Paranoia's dash. Your opponents may panic and waste a critical disable on your spell shield.

Passive · Umbra Blades — Every few seconds, Nocturne's next attack strikes surrounding enemies for bonus physical damage and heals himself. Nocturne's basic attacks reduce this cooldown.
Q · Duskbringer — Nocturne throws a shadow blade that deals damage, leaves a Dusk Trail, and causes champions to leave a Dusk Trail. While on the trail, Nocturne can move through units and has increased Move Speed and Attack Damage.
W · Shroud of Darkness — Nocturne empowers his blades, passively gaining Attack Speed. Activating Shroud of Darkness allows Nocturne to fade into the shadows, creating a magical barrier which blocks a single enemy ability and doubles his passive Attack Speed if successful.
E · Unspeakable Horror — Nocturne plants a nightmare into his target's mind, dealing damage each second and applying fear to the target if they do not get out of range by the end of the duration.
Ultimate · Paranoia — Nocturne reduces the sight radius of all enemy champions and removes their ally vision in the process. He can then launch himself at a nearby enemy champion.

A suggested 5-lane lineup built around Nocturne, based on hero partnerships and role synergy — not win rate.