This achievement is unlocked upon speaking to any NPC in the game after unequipping all weapons, armor, and accessories. The first opportunity is in the prologue. You meet Encel, a gnome. After the scripted dialog with him concludes, press
. Choose inventory -> weapons and unequip the sword by pressing
. At this point, you have not acquired a secondary weapon. Go to armor and unequip all armor. Your beginning armor is a tattered shirt & ragged leggings. If you have equipped any dead enemy drops, remove them. At this point you have no accessories to unequip. Back out and press
to talk to Encel. The dialog does not matter and the achievement unlocks as shown in the below video: