Trample damage

Trample Damage is inflicted in an area around the impact zone of an attack, it is a significant advantage on units possessing it as they may inflict more damage than their attack score alone would suggest. This is due to the fact the damage effects a larger area and potentially more targets. Cavalry move at half their normal speed and take on a V formation. The horses also kick at enemies. You may do a bit less damage but that damage is spread over to neighboring enemy units around a radius of three.

Age of Empires

 * War Elephant
 * Armored Elephant
 * Scythe Chariot

Age of Empires II
The trample Damage is calculated according to the unit's Base Damage / 2.
 * Cataphract (Logistica)
 * Elite War Elephant
 * Battering Ram, Capped Ram, Siege Ram (radius of five)

Age of Mythology
The trample Damage radius is calculated according to the unit's bounding radius plus the attack maximum range. In this area the unit will cause his maximum damage with a reduction of (Base Damage / radius) per meter.
 * Titan (radius of 5,49 meters)

Age of Empires III
In Age of Empires III all cavalry has the option to enter Trample Mode which reduces their damage, increases the damage they receive and gives them a larger area of effect ability for their attacks. It's use in Age of Empires III is questionable, however some units can effectively use it due to outside influences such as Home City Cards or Native American/Native Asian upgrades.

Elephants (excluding Siege Elephants), Brahmin monks, cuirassiers and spahis always use a form of trample attacks, regardless what mode they are in, with exception of "guardian mode". This form of trample does not slow the units down, however toggling trample mode on manually will slow them.