Poison Water

Poison Water is a spell solely usable while the Mephitic spellbook is open. Level 80 Magic is required to cast this spell.

To cast this spell you must have at least one vial of water in your inventory. When it has been cast on a vial of water, the option screen will appear at the bottom of your page (like when cooking) it will give you the choice to poison 1, 5, 10 or X vials of water, turning them into either weapon poison, weapon poison + or weapon poison ++. The chances of it become weapon poison ++ is fairly slim (1/8), most commonly it will either be weapon poison or weapon poison +.

Trivia

 * This spell can only be used to poison water in standard vials, and despite its name, it has no effect on buckets of water or other containers holding water. If the spell is cast on a such item, the following message appears in the chatbox: "You think the poison will lose its concentration in this amount of water, you decide not to cast the spell."
 * It can be quite profitable casting this spell, and it is about 1/6 better xp per hour than high alchemising, although the inconvenience of banking tends to put off players.