Nightcaster

Restore health:
If you are low on health save the game near the mushroom ring.
Leave the game, then load back your saved game file to refill
your health.

Faster health:
To replenish your life, step inside any of the mastery rings.

Rune locations:
Complete the following tasks in the indicated chapter to get the runes:

Get the Light Rune:
Meet the witch and her sister in Chapter 3

Get the Fire Rune:
Beat the Beguiler and his clown in Chapter 4

Get the Water Rune:
Reunite the lost brothers in Chapter 8

Get the Dark Rune:
Reunite the two children with their mother in Chapter 10