The Meaning of Life, the Universe, and Everything.
This is a simple mod that allows the player to create "Tangler Grenades." These grenades are "throwables" (think snowballs) that spawn a cluster of cobwebs where they hit trapping any mobs in that area. The webs will despawn over time such as leaves, so better get moving! Constructing these requires a little redstone and slimeballs. There are some variations that allow for a larger area, glowy webs, or even destroying soft materials to create a "hole" suspending things in the webs.