Given the task definition and input, reply with output. This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

A Turco-Mongol conqueror in Central Asia, Timur (Tamerlane), attacked the reigning Sultan Nasir-u Din Mehmud of the Tughlaq Dynasty in the north Indian city of Delhi. The Sultan's army was defeated on 17 December 1398. Timur entered Delhi and the city was sacked, destroyed, and left in ruins, after Timur's army had killed and plundered for three days and nights. He ordered the whole city to be sacked except for the sayyids, scholars, and the "other Muslims" (artists); 100,000 war prisoners were put to death in one day. The Sultanate suffered significantly from the sacking of Delhi revived briefly under the Lodi Dynasty, but it was a shadow of the former.
What Turko-Mongol attacked and defeated the Sultan of Tughlaq dynasty?