Instant self-bounce/hit of a Ninja Rope weapon drop
From Worms Knowledge Base
This glitch occurs when a worm using a JetPack or ninja rope is descending and travelling in the same direction as an impact detonation weapon dropped from the rope or JetPack. What happens is the weapon spawns above the worm in play, and then hits the worms and detonates. When using the JetPack, this glitch can also happen with weapons that are capable of bouncing on the terrain (such as grenades). In this case the weapon won't detonate but bounce on the flying worm instead.