Activate Sorceress Queen by tapping it, causing a creature an opponent controls to have base power and toughness 0/2 until end of turn.
The creature dies as a state-based action due to having zero toughness because of Elesh Norn's static effect, triggering Sorceress Queen, untapping Sorceress Queen.
Repeat as desired.
You may also repeat this loop whenever a creature enters the battlefield under an opponent's control.
Results
Destroy all creatures opponents control.
Destroy all creatures that enter the battlefield under an opponent's control.