Web Slingers are a rare treasure item found in Scytode Dungeon and Antlion Overlord Pyramid chests. They use Web collected with a Silk Touch sword or Silk Touch Shears as ammunition, and can fire Web from a distance that sticks where it strikes. No damage is inflicted, but it makes for interesting PVP matches.
They can be used to craft the Wither Web Slinger, if you're brave enough to stare down a Black Widow.
Infinity has no effect on the Web Slinger or its variant as Infinity only applies to Arrows.
Wither Web Slinger Edit
Crafted using a Web Slinger, a block of Soul Sand, a Poison Gland and three Wither Webs, the Wither Web Slinger turns into your own personal Black Widow spinneret; allowing you to shoot Wither-inducing webbing at your opponents, ensnaring them and potentially killing them. Works wonders in PVP and in general use.
This variant runs on normal Web. Watch where you step; the Wither Webs will inflict Wither on you, too.