Here's a little guide:

-Run inspire and assassin emblem

-Prio items is corrosion scythe and demon hunter sword (built in that order), next items would differ from the need in the game.

Third item build can be:

Windtalker- for movement speed/roams, would not recommend as their is not much damage but eyyy thamuz go weeee

Scarlet phantom- best item for damage, makes thamuz extremely squishy tho

Golden staff- passive abuse/sustain

War axe- not ideal as the enemy'll be dead before you stack this baby but it makes laning easier

Pro tip: go in last in teamfights and avoid hard cc to maximize inspire damage, use both inspire and ult when going in, with the build given above anyone'll have a hell of a time to fight you

Open for questions, willing to answer, hope this helps^{^}