Larian Studios Forums Divinity - Original Sin Divinity - Original Sin - Enhanced Edition Where to find adept level summon skillbooks?

I finally found undead decapitator at the end of the mines but summon ice elemental and summon air elemental are nowhere to be found. Are these only attainable through crafting?

Found summon air elemental at the homestead air goddess I think ice was in front of chest in hieberheim trap door passage to castle

I usually craft most of them by end of Cyseal.

Blank scroll+element=blank elemental scroll
Blank spell scroll+blank spell scroll=blank skill book
Blank skill book+spell scroll of same element=skill book.