The Tepoztopilli was much like the preferred Aztec weapon, the Macuahuitl, albeit with a much longer handle and a curved head.
Grooves were dug into the head of the wooden spear, and were lined with obsidian blades. Some versions of the Tepoztopilli likely had a single pointed blade affixed to the top, according to Castillo. Alongside the bow, sling, and club, this weapon was utilized by commoner auxiliaries in battle. In general, spears are relatively easy to use with little to no training and they allow a combatant to keep his enemy at a distance. However, generals and other high ranking soldiers are also depicted using this weapon in the Codex Mendoza.
Ross Hassig classifies this weapon as a halberd, as opposed to a spear, because the blades on its sides mean that it was intended for swinging in addition to stabbing. Hypothetically, it could have been thrown in battle, but it was likely cumbersome to carry more than one or two and the Atlatl could have been used more effectively in this regard. As such, it was probably used mostly as a melee weapon.
Depictions in the Codex Mendoza and descriptions by the conquistadors show that it was probably about 5 to 9 feet in length, although that likely varied depending on the situation. Bernal Diaz described some of the spears as “longer than our lances”. That being said, there is no evidence to suggest that pikes or the Mesoamerican equivalent of pikes were used (probably a result of no cavalry in the New World).