Dungeoneering is a skill that consists of killing NPC's for tokens and experience.
To begin this skill, you will want to visit the "More Skills Teleport" in the "Magic Spellbook". Make sure you bring some armour, weapons and food to begin killing the NPC's. You will receive more XP and tokens, depending on which monster you attack.
Best Dungeoneering Monsters To Fight
Avatar of Creation - Highest / Best (HP) (240,000 Xp, and 16 Tokens)
Solus Dellagar - Medium / Average (HP) (152,000 Xp, and 13 Tokens)
Ice Giant - Lowest/Worst (HP) (88,000 Xp, and 7 Tokens
"Dungeoneering Tokens", can be used to exchange for the following items ;