Lava dragons are prone to Magic and Fire spells, so it's recommended to use them, but the Trident is the ideal weapon of choice. At 74 Agility and with the hard Wilderness Diary completed, an Agility shortcut becomes available for quickly accessing the dragons and escaping an onslaught. You can use a Games necklace to teleport to the Corporeal Beast's lair, go north to the shortcut, kill some dragons, leave via the shortcut, go south into level 30 Wilderness, teleport to Edgeville with an Amulet of glory, and repeat. Otherwise, you'll just have to traverse the deep Wilderness going to and from the Mage Arena bank, which is more dangerous and risky.
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