Alteration Ritual Spell

You have mastered Alteration spells, what is next?

Walkthrough
Once you have reached 90 skill points in Alteration, a new conversation option is revealed when speaking with Tolfdir. If you ask him


 * "What else is there to be learned about Alteration magic?",

he will mention that he has been working on a new spell, but requires Dragon Heartscales obtained with a special dagger known as Kahvozein's Fang.

He will then tell you where you can retrieve the dagger. This location could be any of the following:


 * Forelhost
 * High Gate Ruins
 * Lost Valkygg
 * Ragnvald
 * Valthume
 * Volskygge

Proceed to whichever dungeon Tolfdir mentions and retrieve it.

Note: This dagger can be found by simply exploring Skyrim, so do not be surprised if no dagger location is mentioned by Tolfdir.

Use Kavohzein's Fang to collect Heartscales
Next, find a dragon. It does not usually take very long for one to appear. Once it has been defeated, use the dagger to retrieve the heartscales.

Bring Dragon Heartscales to Tolfdir
Return to Toldir who will reward you with Spell Tome: Dragonhide. Thereafter, he will also sell Spell Tome: Mass Paralysis.

Der Veränderungsritualzauber