This power allows the werewolf to draw upon the Spirit of Fenris, filling himself with unbridled rage. While raging, you gain a +10 bonus to Attack and Defence, +5 Damage and +1 to Speed for each rank you have in this power. The rage lasts for 30 seconds, and also negates all pain penalties while active.
Unfortunately this power will also leave the werewolf slightly weakened for a while afterwards, but in the heat of battle it is often considered worth the cost. For 30 seconds after the rage has finished, you will suffer a penalty of -10 to your Attack, Defence and Damage, and -5 to your Speed.
If you also have the Berserker Rage talent, then the bonuses from that will be applied at the same time as your Spirit of Fenris, although this power will be used to determine the duration. If you have the Tireless Rage talent, then it will also negate the exhaustion penalties for this power.