This lens attached to your face makes you a deadly hunter at night, able to bring down your prey with arrows from the dark.
Lore: Warforged can attach a monocle of the ebon hunter to their temples; it improves their vision at night (Knowledge [arcana] DC 15). The monocle also help warforged archers hit their targets, whether it’s dark or not (Knowledge [arcana] DC 20).
Description: A monocle of the ebon hunter is a coin-sized lens of smoky crystal, set in a wire frame that attaches to your head near the temple.
When you have a ranged weapon in your hands and are in shadowy illumination or darkness, the wire frame around the monocle glows faintly red-orange, like embers in a campfire. Peering through the monocle, you see auras surrounding your foes within 60 feet. Bright sparks on the periphery of the aura indicate weak points in your enemies’ defenses; you’re more likely to strike a telling blow if you can hit those points.
Prerequisite: A monocle of the ebon hunter is an embedded warforged component, so it functions only for warforged characters.
Activation: A monocle of the ebon hunter occupies space on the body as a set of lenses or goggles, providing its benefits automatically as long as it’s embedded. Embedding or detaching a monocle is a standard action that doesn’t provoke attacks of opportunity. You can wear only one monocle at a time.
Effect: Monocles of the ebon hunter come in two varieties. A lesser monocle grants a +1 competence bonus on ranged attacks made against targets within 60 feet. A greater monocle grants a +2 competence bonus on ranged attacks on targets within 60 feet, and a +1 competence bonus on damage rolls if those ranged attacks hit.
Both versions of the monocle of the ebon hunter grant darkvision out to 60 feet.
Aura/Caster Level: Moderate transmutation. CL 6th.
Construction: Craft Wondrous Item, darkvision, true strike, caster must be 6th level or higher, 9,000 gp (lesser) or 19,000 gp (greater), 720 XP (lesser) or 1,520 XP (greater), 18 days (lesser) or 38 days (greater).
Price: 18,000 gp (lesser) or 38,000 gp (greater).
Source: Explorer's Handbook