Originally Posted by Junts

Explaination of the weapon glitch:

Have you ever noticed how if you swap weapons right at the start of an animation, you can do an attack using an animation from the wrong weapon type? Throwers are particularly prone to this. Switch weapons right as you throw and you will often do an animation where you fling your normal melee weapon.

This isn't typically a problem becuase we use returners. However, it can be a problem when using stacks of finite objects, like the vials and boulders, because the number of your melee weapons in the stack is 1 - if this happens with those weapons, they're gone.

If people ever used those 20 stacks of +5 throwing x's, this would happen more often and anywhere. For safety in blighted and abbot, switch to a scroll stack or something before switching to a melee weapon when swapping quickly between the limited-item stacks and your melee weapon. If you are attacking rapidly with a boulder stack, you can fling away your main weapon permanently when you equip your real weapon again.

Specifically in Tomb of the Blighted and Abbot.