Level R: 40 - Fire R: 100 - Light.R -10 - Pois. R. 100 - Spirit 100 - Attack/defense 86/94 - Damage 238-714 - AC 329 - Health 6300 - Sight 12
Weaknesses differ between the species, with the blues being particularly susceptible to lightning based attacks. However, if one is caught observing the dragonriders, one should be prepared for ranged attacks of fire, lightning, poison, and even freezing blasts! Running is a poor option as they are extremely fast as well. Easily the most dangerous inhabitant of the wastelands, and should be treated as such.
From Sir Toejam's bestiarium. So, I'd go for lightning. My strategy was different, I fought as a mage, sorry - no further help possible.
Kiya