ok before you all do the knee jerk "no weapons" reaction please note that most weapons are for pvp this is for pve it can only hurt ghasts some hostile mobs so its more a tool than a weapon
Name: GhastBuster
Description: a special built gun for conquering the nether and containing ghasts the ghast buster fires a long range non-block-breaking beam that only hurts ghasts 10 seconds of exposure will kill a ghast(is that to long?). also when you equip the ghast buster and a batpak/lappak at the same time for the first time you get the achievement "who ya gonna call?"
EDIT: do to popular demand the ghastbuster also harms undead (zombies, skeletons, pigmen), also when you cross the beams in smp you get a "don't cross the streams achievement" and you may spontaneously explode
Recipe:
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