How to add AP defense without armor

Displacement Cloak

+30 Ability Power 50% Mana Regen 10% Move Speed 5% CDR

Unique Passive - 8% Heal and Shield power Unique Passive - Displacement - Dash skills targeted at you miss by 50 units (50% chance).

Build: + + 750 gold

Note - Would only affect TARGETED dashes like Talon's Q or Yi's Q, not AoE like Sion or Galio ult or Kha'zix's E.