When Soul Warden enters the battlefield, Terror of the Peaks triggers, dealing 1 damage to you.
Darien triggers, creating a 1/1 Soldier creature tokens.
When the Soldier enters the battlefield, Terror of the Peaks and Soul Warden trigger.
Resolve the Soul Warden trigger, causing you to gain 1 life.
Resolve the Terror of the Peaks trigger, dealing 1 damage to you.
Repeat from step 3.
This looping engine brilliantly turns self-inflicted damage into an endless parade of reinforcements, fueled entirely by the passive life-cushion of Soul Warden. When Terror of the Peaks strikes you, Darien, King of Kjeldor steps in to convert that pain into a fresh 1/1 Soldier token. That new arrival triggers Soul Warden to patch up your life total while simultaneously causing Terror of the Peaks to deal another point of damage to you, seamlessly restarting the loop.