Mormon tells us that the Lamanites used tricks of their own to entrap the Nephites (v. 27) and spells out two of the attempts: a nighttime effort to surround the Nephites, and getting the Nephites drunk. Neither attempt worked. It is probably not coincidental that these Lamanite attempts parallel successful Nephite tactics. It is also certain that Mormon intends that we see the Nephites as superior to the Lamanites, not only in deploying the tactics but being wary of them.
Redaction: The Lamanites may have used other tactics, but Mormon records only two, both of them methods Moroni had already used (Alma 52:22; 55:9–12). Mormon’s purpose is to record not the tactic but Yahweh’s favor. These “stratagems” work for the Nephites, but not for the Lamanites, because Yahweh is with the Nephites.