try this shaco build

Infinity edge + 50% crit with 30% crit damage from runes increases critical to 320% from the back. Rabadons deathcap+magic pen runes Lich bane Hextech gunblade Muramana Sorcerers boots

1. Start building tear to get stacks up for the mid and late game.
2. Build or start building hextech
3. Infinity edge
4. Rabadons deathcap
5. Lich bane

Boots and muramana whenever. This should do around 1100 damage with Deceive (Q) from back E would do around 1000 with muramana active, with spellvamp its great combo.

Please try it out and see how it works, then post back.