Half-dragons are only rarely the result of dragons mating with other creatures—most are the result of strange magical experiments. In most cases, a successful creation breeds true with others of its kind, as with the dreaded dracolisk.
“Half-dragon” is an inherited or acquired template that can be added to any living, corporeal creature (referred to hereafter as the base creature). A half-dragon retains all the base creature's statistics and special abilities except as noted here.
CR: Same as the base creature + 2 (minimum 3).
Armor Class: Natural armor bonus improves by +4.
Speed: A half-dragon has wings. Unless the base creature has a better fly speed, the half-dragon can fly at twice the creature's base land speed (average maneuverability).
Melee: A half-dragon has two claw attacks and a bite attack. If the base creature can use manufactured weapons, the half-dragon can as well. A new claw or bite attack deals damage as appropriate for the half-dragon's size (see “Natural Attacks”).
Special Abilities: A half-dragon retains all the special attacks of the base creature and gains a breath weapon usable once per day based on the dragon variety (see below). The breath weapon deals 1d6 hit points of damage per racial HD possessed by the half-dragon (Reflex half; DC 10 + 1/2 creature's racial HD + creature's Con modifier).