Energy

Three attributes:

Attribute	Formula	Used for
Mana	1/2 level + Cha	Supernatural power (innate or item-based)
Focus	1/2 level + Wis	Feats of mental focus and discipline
Stamina	1/2 level + Con	Feats of physical prowess and endurance

Mana

Used to manifest Powers. Feats exist to enhance and modify powers by spending Mana.

Used by feats, many of them granted by the Concentration skill, but many others besides, such as:

Called Shot (Ranged Weapons): Increases damage by +100%, costs 1 Focus, stackable.
Double Shot (Ranged Weapons): Fire two attacks instead of one, at same or different targets in same arc. Costs 1 Focus.
Nearly Missed (Dodge): Converts a failed Dodge attempt into a partial success (you suffer 50% damage). Costs 1 Focus.
Instant Aim (Ranged Weapons): Use the Aim action as a free action; costs 1 Focus.
Reactive Counterspell (Concentration): Counterspell as an immediate action; costs 1 Focus.

Used by feats, many of them granted by the Fortitude skill, but many others besides, such as:

Power Attack (Melee Weapons): Increases damage by +100%, costs 1 Stamina.
Critical Block (Block): Adds +50% block to a block attempt, pass or fail. Costs 1 Stamina.

The rate at which you restore energy depends on your activity level:

Activity Level	Description	Energy recovery rate
Heavy	Combat, forced march, continuous spellcasting, etc	None
Light	Walking, riding, spell research	1 point per 60 minutes
None	Sitting, resting, sleeping, meditating	1 point per 15 minutes

All 3 types of Energy are recovered at the same rate simultaneously.