Constitution
From Fire Emblem Wiki
Constitution (also known as Build and is shown as Con in game) in Fire Emblem is a representation of how big a character/unit is. Constitution is also affected by characters that usually have Mounts (Pegasus Knights, Cavaliers, etc). Constitution determines which weapons units can carry without suffering a penalty to their attack speed in battle, as well as which other units they can rescue and capture.
Similar to Movement, this stat only increases with the use of an item or through class change.
The item Body Ring can increase the Con stat by 2, just as the Boots and the Talisman increase Movement and Resistance by 2 respectivly.
[edit] Constitution and Attack Speed
In the Gameboy Advance Fire Emblem games, Attack Speed is determined by taking the unit's Con and subtracting the weight of the weapon equipped. Negative numbers result in a penalty to skill and speed for the unit. It should be noted that positive numbers Do Not result in a bonus to attack speed.
[edit] For example:
Nino's Con is 3. The weight of a Fire tome is 4. Therefore Nino's Con (3) subtracted by Fire's weight (4) yields a result of -1. This in turns means that when Nino enters combat, she will suffer a penalty of 1 Skill and 1 Speed.
Note that Attack Speed penalties do not result in permanent subtraction from a character's stats.
In modern Fire Emblem games such as Path of Radiance, Strength is used in place of Con for calculating Attack Speed.
[edit] Rescue Stat - Mounted vs. Nonmounted Units
In the case of nonmounted units, the Rescue, or Aid, stat is directly proportional to the Constitution of the unit in question. As the unit's Con rises, so does their Aid. This allows the unit to rescue heavier units.
In the case of Mounted units, Aid and Con are inversely proportional. As Con rises, Aid is lowered. The unit loses the ability to rescue heavier units.
