Racial Enemy Against

Increases damage done to the enemy race.

Racial Enemy comes with a specific boost in percent, which is simply multiplied into the damage modifier (ie damage made in an attack.)

For all units currently in use, this boost is 50%. This means that the unit with the ability will simply have a 50% boost to all its damage rolls against units of the enemy race. Notably this is not what the ATTDEF wiki page says.