Blue Dragons are relatively easy to kill, and you can use all three attack styles to do so. However, these dragons are the weakest against stab and range attacks, so choosing either a ranged or melee armor setup is highly recommended. 

Recommended Armor

Here is a setup example for each attack style, followed by some suitable cheaper replacements.

Range Setup

• Slayer Helm. Armadyl Helmet, Robin Hood hat.
• Necklace of Anguish. Amulet of Fury, Amulet of Glory.
• Armadyl Chestplate. Black or Blessed D’hide.
• Pegasian Boots. D’hide Boots, Snakeskin Boots.
• Barrows Gloves. Blessed D’hide Braces.
• Dragonfire Ward. Anti-dragon shield, Twisted Buckler.
• Dragon Hunter Crossbow. Armadyl Crossbow, Dragon Crossbow.
• Ava’s Assembler. Ava’s Accumulator.
• Archer’s Ring. Ring of Suffering, Granite Ring.
• Amethysts Broads. Runite Bolts.

Magic Setup

• Slayer Helm. Black Mask, Ancestral Hat.
• Occult Necklace. 3rd Age Amulet, Amulet of Fury.
• Ancestral Robe top. Ahrim’s robe top, Infinity top.
• Eternal Boots. Infinity Boots, Wizard Boots, Boots of Darkness.
• Tormented Bracelet. Barrows Gloves, Infinity Gloves, Dragon Gloves.
• Ancient Wyvern Shield. Anti-dragon Shield, Arcane Spirit Shield.
• Trident of the Swamp. The staff of Light, Trident of the Seas, Slayer’s Staff.
• Imbued God Cape. God Cape, Ardougne Cloak, Ghostly Cloak.
• Seers Ring. Beacon Ring, Lunar Ring.
• Any God Blessing. 

Melee Setup

• Slayer Helm. Black Mask, Helm of Neitiznot, Serp Helm.
• Amulet of Torture. Amulet of Fury, Amulet of Strength.
• Bandos Chestplate. Fighter Torso, Obsidian Platebody.
• Bandos Tassets. Obsidian Platelegs, Barrows Platelegs, Dragon Platelegs.
• Primordial Boots. Dragon Boots, Guardian Boots.
• Barrows Gloves. Rune Gloves, Granite Gloves.
• Dragonfire Shield. Anti-dragon Shield.
• Ghrazi Rapier. Zamorakian Hasta, Abyssal Dagger, Abyssal Whip.
• Fire Cape. Mythical Cape, Skill Cape, Obsidian Cape.
• Berserker Ring. Treasonous Ring, Ring of Suffering, Granite Ring.
• Any God Blessing. 

Inventory

-A couple of ranging potions

-Some runes to cast high or low alchemy spells

-A herb sack

-Falador teleports

-One dose of stamina potion

-A shark to heal your hit points

-A dusty key (not needed if you have 70 Agility)

-A shield switch for safe spotting

-Extended anti-fire potion (if you are using melee)

• To get a dusty key, get yourself to Taverley Dungeon and run to the Black Knight’s Base. All you need to do is kill the jailer, and he’ll drop the jail key. Use it on the southern door to access Velrak, the explorer, follow the dialogue, and he’ll give you a dusty key.

Blue Dragons Location

Taverly Dungeon

From Falador West Bank, use the Agility shortcut, and it will take you just south of Taverley Dungeon. Run your way towards it, and once you are there, climb down the ladder.

If you have 70 Agility, use the obstacle pipe to your right.

If you don’t have 70 Agility, drink a dose of your stamina potion and start running north. You will notice some armor pieces on the east side of the wall; spam click the prison door to prevent the guards from attacking you. Once you are inside, go south and open the next door. Keep running through the passageway heading east.

Once you reach a break on the path, run south. There will be another break on the path, this time head west. You will start seeing some lava and scorpions as you come closer to the Blue Dragons room. 

Cross the bridge, run north, and once you past the lesser demons, use your dusty key on the gate to your left. You will now access the Blue Dragons.

Yanille

Safe Spots

If you are using a melee setup, go ahead and drink a dose of your extended anti-fire potion and your superset. If you are on a Slayer task, head to the southern part of the room.