The Complete Arcane supplement offers not only a wealth of new spells, but also plenty of prestige classes that make great NPCs and great tips about running campaigns heavy on arcane elements. Below are ten reasons why Complete Arcane is a great resource for DMs.

10. Warmage: So your PCs think mages can't hold their own on the battlefield? They'll sure be surprised the first time they encounter a warmage NPC who has been trained especially for combat. The warmage, one of three new base classes introduced in Complete Arcane, can cast spells while wearing some kinds of armor with no arcane spell failure chance. Furthermore, he deals extra damage with his damage-producing spells and can increase their power on the fly via the new Sudden feats, which he gains as bonus feats.

9. NPC Prestige Classes: Complete Arcane introduces a host of arcane prestige classes that make great NPCs. The argent savant is a master of force magic, the effigy master can create armies of constructs to serve him, the initiate of the sevenfold veil takes the power of prismatic spells to a whole new level, and the mindbender can effectively create permanent thralls through her charm and dominate spells.

8. Spell Duels: Do your PC wizards make a practice of flaunting their magic in public to the annoyance of others? If one of those annoyed is another wizard, the errant PC could find himself challenged to a spell duel -- possibly by a very powerful opponent.

7. Spell-Like Ability Feats:Complete Arcane offers a wealth of new feats, including several that grant a few minor spell-like abilities. Communicator grants communication spells, Insightful grants detection effects, Necropolis Born grants necromancy spells, Night Haunt grants effects that mimic ghostly maneuvers, Soul of the North grants cold effects and cold resistance, and Spell Hand grants manipulation spells. Use them to give your NPCs an unexpected twist!

6. Arcane Organizations: Organizations are always great sources for adventure hooks, and both PCs and NPCs benefit from membership. In addition to the usual mages' guilds, colleges of wizardry, and societies of magic, Complete Arcane offers three new organizations that also support various prestige classes. The Arcane Order is a college that offers members access to its Spellpool. The Seekers of the Song celebrate the primal music, and members of the Wayfarers Union provide teleportation services for their communities.

5. Tournaments Arcane: Need an interesting event for your campaign world? How about a tournament for arcanists? Complete Arcane offers four versions of such tournaments -- the Spire Perilous, the Grand Illusion, the Wizard's Menagerie, and the Dweomerlist.

4. Monsters of Magic:Complete Arcane offers a variety of monsters of particular use to arcane spellcasters. The effigy creature is a magically animated automaton built to resemble another creature. Elemental creatures include the elemental monolith (a powerful elemental prince), and a remake of the elemental grue. Updated versions of the pseudonatural and spellstitched creatures are also included.

3. Feats for Arcanists' Enemies: If the wizard in your party has become famous, she's probably accumulated some enemies. Complete Arcane offers a series of feats particularly useful to those who make careers of dispatching mages. The Mage Slayer feat prevents spellcasters threatened by the user from casting defensively. The Pierce Magical Concealment feat allows a character to disregard the miss chance granted by various arcane effects and pick out the real caster in a mirror image effect. A character with the Pierce Magical Protection feat can ignore all his enemy's magical bonuses to AC and instantly dispel them the first time he deals damage.

2. Magic Items for Campaign-Building: Complete Arcane offers several new magic items of special interest to DMs. The rod of interference, which suppresses the function of all the target's magic items for 1 minute, is a great way to surprise PCs who amass items. The thought bottle, which stores thoughts, memories, experience, and spells, can be a great basis for an adventure. And if you need a way to get the PCs in over their heads quickly, just convince one of them to sign a contract of Nepthas to perform a specific task.

1. The Arcane Campaign: Want to include more magic in your campaign, or get some tips on running high-magic games effectively? Complete Arcane provides a wealth of information on fitting more magic into an ongoing campaign, as well as tips on pacing the game, designing adventures for spellcasters, and world-building with magic.