I've been asked for the locations of the dragons used to obtain the scales, you must have the previous level scale when killing these, i.e. you need scale 8 if you want to kill dragon 9, otherwise it wont drop a scale.
Eos-I -50- -Roan Harbor(66,243)-
Eris-II -55- -Undead Canyon(114,171)-
Eros-III -60- -Dwarves' Forest(80,174)-
Naiads-IV -65- -Doomed Jungles East(213,157)-
Kalypso-V -70- -Doomed Jungles West(159,283)-
Simois-VI -75- -Sand Castle(52,117)-
Achelous-VII -80- -Cursed Desert(275,106)-
Axius-VIII -85- -Demigod Prairie(258,141)-
Glaucus-IX -90- -Nordic Lands(53,256)-
Triton-X -95- -Burning Land(150,192)-
Leucothea-XI -100- -Everstill Lands(113,108)-
Nereids-XII -105- -Plain of Despair(128,224)-