Alma 52:21 - 52:25
Alma 52: 21 And it came to pass that Moroni, having no hopes of meeting them upon fair grounds, therefore, he resolved upon a plan that he might decoy the Lamanites out of their strongholds.
With the refusal of the entrenched Lamanites in Mulek to come out and fight on level ground, Moroni came up with a way to lure them out of the town.
Alma 52: 22 Therefore he caused that Teancum should take a small number of men and march down near the seashore; and Moroni and his army, by night, marched in the wilderness, on the west of the city Mulek; and thus, on the morrow, when the guards of the Lamanites had discovered Teancum, they ran and told it unto Jacob, their leader.
Teancum was ordered to march with a small force near the seashore in sight of Mulek the next morning. Moroni, on the other hand, with the remainder of both armies, march through the night in wilderness unseen to the west side of Mulek. In the morning a century on the city walls saw Teancum’s movements and reported them to Jacob the Lamanite commander.
Alma 52: 23 And it came to pass that the armies of the Lamanites did march forth against Teancum, supposing by their numbers to overpower Teancum because of the smallness of his numbers. And as Teancum saw the armies of the Lamanites coming out against him he began to retreat down by the seashore, northward.
The Lamanites seeing the small force of Teancum came out of the city to attach and destroy Teancum. The Lamanites thought they could wipe out this small force of Nephites and then get back to Mulek quickly. However, Teancum saw the attacking Lamanites he had his men move with all speed northward by the seashore.
Alma 52: 24 And it came to pass that when the Lamanites saw that he began to flee, they took courage and pursued them with vigor. And while Teancum was thus leading away the Lamanites who were pursuing them in vain, behold, Moroni commanded that a part of his army who were with him should march forth into the city, and take possession of it.
When the Lamanites saw Teancum starting to run away, they took out after them. However, they could not catch Teancum. What the Lamanites did not know was that the Moroni had sent part of his force to take Mulek from the small garrison that was left in charge of Mulek and the rest were coming up on the Lamanite rear.
Alma 52: 25 And thus they did, and slew all those who had been left to protect the city, yea, all those who would not yield up their weapons of war.
The Nephites took the city and killed all the Lamanites who resisted.