Unimpeded Eldritch Crossbow

This is my second favourite munchkin item. The Unimpeded Eldritch Crossbow shows through walls.

Ruling for Pathfinder

This +5 heavy crossbow can fire through solid objects. Firstly the aiming mechanism of this heavy crossbow features a crystalline lens that allows the viewer to see and aim through solid objects (cf. Ring of X-ray vision). Secondly, the tiller ends in a black orb, into which the fired bolts disappear before reappearing in front of the intended target by teleporting across any obstacle. Shooting across armor is a tricky shot (–5), but is a touch attack (flatfooted touch attack if surprise round). Magic darts can be used and are unaffected by the process.
Imbued with teleport, true seeing
Making cost ~50,000 gp (lvl 5+6 spells)

Inspiration

This is clearly the Star Trek DS9 rifle that teleported its bullets, the TR-116_rifle.

Field trial

Yes, I gave my players this item. It is not the maddest item, mind you, I even gave them a lightsaber that sliced through anything, but on a crit fail would sever the wielder's limb (it was never used).
This item resulted in a mage being shot while on his bone rocking chair reading a rotting paper and smoking a pipe with an eerie green fumes. The character was buffed up and the shot fired. Missed the headshot in the first go. Only in the try did he manage, but got a near TPK wooping.