Brutal green dragons attack with melee, magic and dragonfire. If you choose to use ranged or magic, you don't have to deal with the melee attacks because the dragon will never move towards you. The fight can still be difficult however, because the dragon's magic attack is far more accurate than those of mithril dragons. Protection from the dragon's breath is always necessary when fighting these dragons, since they can attack with dragonfire from long range. To that end, you should use an anti-dragon shield, antifire potions/mixes, or a dragonfire shield.