Form of the Dragon I
Size becomes Huge (15' space, 10' reach)
+10 size bonus to Strength, +8 size bonus to Constitution, +8 natural armor bonus, fly 120 feet (poor), blindsense 60 feet, darkvision 120 feet, a breath weapon (12d8) every 1d4 rounds, DR 10/magic, frightful presence (DC equal to the DC for this spell), and immunity to one element (based on choice). You also acquire the vulnerabilities, if any.
Black dragon: 60-foot line of acid, resist acid 20, swim 60 feet
Blue dragon: 60-foot line of electricity, resist electricity 20, burrow 20 feet
Green dragon: 30-foot cone of acid, resist acid 20, swim 40 feet
Red dragon: 30-foot cone of fire, resist fire 30, vulnerability to cold
White dragon: 30-foot cone of cold, resist cold 20, swim 60 feet, vulnerability to fire
Brass dragon: 60-foot line of fire, resist fire 20, burrow 30 feet, vulnerability to cold
Bronze dragon: 60-foot line of electricity, resist electricity 20, swim 60 feet
Copper dragon: 60-foot line of acid, resist acid 20, spider climb (always active)
Gold dragon: 30-foot cone of fire, resist fire 20, swim 60 feet
Silver dragon: 30-foot cone of cold, resist cold 30, vulnerability to fire