Torens triggers, creating a 1/1 Human Warrior creature token.
When Kor Skyfisher enters the battlefield, it triggers.
Holding priority, activate Earthcraft by tapping Kor Skyfisher, untapping the Plains.
Resolve the Kor Skyfisher trigger, returning it to your hand from the battlefield.
Activate the Plains by tapping it, adding .
Activate Earthcraft by tapping the Human Soldier token, untapping the Plains.
Repeat.
This clever loop turns Kor Skyfisher into a self-returning engine by leveraging Earthcraft to untap your mana source using creatures that would otherwise just sit idle. Every time you cast Kor Skyfisher, Torens, Fist of the Angels steps in to reward your creature spell by generating a 1/1 Human Soldier token with training. Earthcraft then allows you to tap that fresh token to untap the basic land you just used, fueling the next iteration while Kor Skyfisher's own enters-the-battlefield trigger bounces itself right back to your hand.