In J.R.R. Tolkien’s legendarium, which god destroys Númenor?

In J.R.R. Tolkien’s legendarium, Eru Ilúvatar destroys Númenor.

The event occurs in the Akallabêth, Tolkien’s account of Númenor’s downfall. The island kingdom’s rulers become increasingly ambitious and resentful of the immortal Valar. Under Ar-Pharazôn, Númenóreans invade Aman, the Undying Lands, seeking the immortality they believe the Valar possess.

Eru, the supreme creator, changes the shape of the world. Númenor is overwhelmed and sinks beneath the sea, while Aman is removed from the ordinary physical world. The catastrophe also changes Arda from a flat world into a round one in Tolkien’s later conception.

Readers sometimes assign the destruction to Sauron because he encouraged Númenor’s rebellion and was present there. Sauron was an instigator and captive adviser, however, not the power that carried out the final destruction.