Glacial Ward

As a reaction to being attacked or taking damage, you can conjure a protective block of ice around yourself. For the duration you become immune to attacks and spells, unable to cast any spell or take any actions. While you’re inside this block of ice, you regain 2d10 hit points per turn, and creatures that enter or leave the 20-foot area around it must make a Constitution saving throw, taking 4d6 glacial damage on a failure, or only half as much on a success.

At Higher Levels. When you cast this spell by spending Mana points equal to a 6th-level spell or higher, the healing increases by 1d10, the damage by 1d6, and the area of effect increases by 5 feet for each spell level above 5th.