Big Dragon Boss - Hard as hell if you don't get the pattern down.
Thankfully follows the pattern all the way through the fight and with a good enough weapon (the Katar is more than enough) can be killed before the second loop properly starts.
Be aggressive and keep attacking when you can.
1. First attack is mini fireball spread then a windball spread, use salamander and whale away until the brief pause, swap to sylph and continue until Narse closes his mouth.
2. Dodge back when he freezes for a second as he'll jump forward. Keep the attacks going while he's still on the ground.
3. He'll launch into the air and rain dark meteors down, hard to dodge as the are random and will when they hit the ground and roll to the wall.
4. Beam of Dark you'll need to get to the wall and levitate as high as possible, keep up the damage inbetween.
5. Last attack type, flys to the back of the screen and fires more meteors, you need to swap sides of the room at this point as he'll land and reverse the fight.
Rotate back to 1 and continue until he falls and you get your achievement.