Meditation.

Meditation is the fourth skill John gained on the day he woke up with his powers.

Meditation
Meditation: stay motionless with your eyes closed and empty your mind. Nothing else can be done while meditating.

Gain: 

Hp regen x2

Mp regen x3

Increased chance to discover new magic skill

History
John gained the skill after closing his eyes in Mrs. Flung's class.