Perfect Hunter's Weapon
This weapon ignores cover and concealment when its magic is activated.
Weapon: Any ranged
Enhancement Bonus: attack rolls and damage rolls
Critical: +1d12 damage per plus
Power Daily (Standard Action)
When you use this power, you automatically pinpoint the location of all creatures within 10 squares of you, even if line of sight or line of effect to those creatures would normally be blocked. This pinpointing lasts until the end of your turn. You can target any one of those creatures as if it did not have cover or concealment. You can then make a ranged basic attack with this weapon with a +5 bonus to the attack roll.
Published in Player's Handbook, page(s) 235.