Extreme magic

Extreme magic potions are made by players using the Herblore skill. They require a Herblore level of 91 to make. When drunk, the player receives a boost of 7 magic levels, which decreases over time. Each magic level over the base level gives 3% extra damage when attacking using magic. This stacks with the extra 10% boost from certain magical staves. With the Staff of light, 7 level boost from this potion, an Arcane stream necklace and a Hexcrest or Full slayer helmet worn against an assigned slayer monster, the theoretical (if all of those things stack, which is not confirmed at the moment) damage percentage boost would be 66%, allowing the player to hit up to 464 with Fire Surge and 498 with Ice Barrage. With a Chaotic Staff, the damage percentage boost would be 71%, theorically allowing you to hit 478 with Fire Surge and 513 with Ice Barrage. Additionally, if a player is wearing a Fire cape, and has a Slayer task of Ice strykewyrms, that player can do another 2x damage while using a fire spell. So in theory, if a player is wielding the Staff of light, a Hexcrest or Full slayer helmet, an Arcane stream necklace, and a Fire cape while using an Extreme magic potion, and Fire Surge on Ice strykewyrms, that player could have a maximum hit of over 1120.

A Magic potion (3-dose) and a Ground mud rune are the ingredients required to create an extreme magic potion. Making an extreme magic potion gives 250 Herblore experience. It cannot be made with the assistance of other players.

An extreme magic potion along with an Extreme attack, Extreme defence, Extreme ranging, and Extreme strength, can be used with a clean torstol at 96 Herblore to make an Overload potion.

When first released, the Extreme and Overload potions could be used in PvP situations, but within 48 hours, this was changed so they cannot be used in any PvP situation, dangerous or safe; however, as of the 17th November 2009, Overload along with all other untradeable potions, can be used in safe PvP activities. At first extreme magic potions did not boost one's Magic level; instead, they boosted the player's magic damage by 40%. This was changed to the current 7 level boost, resulting in 21% magic damage bonus.

Note also that a Wolpertinger's special move, Magic Focus, also provides a seven-level Magic bonus. Given this, higher-level Summoners would be better off using Extreme Magic only as an ingredient in the Overload potion, and relying on Wolpertingers for Magic boosts. Furthermore, Magic Focus works in dangerous PvP areas/worlds and the wilderness but Extreme Magic does not (except for at King Black Dragon, Corporeal beast and one or two spaces away from the wilderness wall).