Mindspike glitch

On 10 February 2012, a glitch involving the use of a mindspike staff allowing any player wielding one to kill any NPC with it. The NPCs would always drop bones. The glitch occurred after the Burthorpe graphical update, but was first discovered on 10 February, and hotfixed less than an hour after its discovery.

This glitch was widely used in pranks by players to kill other players' pet cats. This would cause a player to lose their cat on death, meaning they would have to get another kitten and raise it back to 100% growth. However, it would not cause other pets to die; they would simply spawn bones on the ground and not vanish. The glitch worked by clicking the special attack bar and then casting any combat spell on an NPC that was previously unattackable. Bankers, familiars, and random event NPC's could all then be attacked in this fashion. Due to this glitch, it was discovered that most non-combat NPC's have 1 life point. This glitch was also used to temporarily break bots, by killing the Dungeoneering banker.

A few non-combat NPCs, like cats, would attack back using this glitch. This is likely because cats are able to fight in the Ratcatchers quest, so have an amount of life points set by Jagex.