Adding to the Zombie Guide to the Apocalypse, here's an AA Zombie concept build that worked quite well up through L20 (now playing level 21+).
This build is based on Strimtom's Acid Arrow. I recommend checking out his fun post to learn more about running a solid AA build.
Level 20 Wizard (optional, 17 Wizard/3 Rogue for trapping, evasion, and extra sneak attack damage. Also, level 9 Wiz spells are not too useful for this build.).
Race: Any Elf or Half-Elf with AA in the Racial Enhancement tree.
Feats: Manyshot (with Point Blank and Rapid Shot), Spellcraft Skill +3, Maximize, Empower, Extend Spell, Mental Toughness, Improved Mental Toughness, Toughness, Weapon Focus - Ranged, and Precision.
Primary Abilities, in order: Dexterity, Constitution, Intelligence
Enhancements:
- Racial: 24 points to get Arcane Archer (increase To Hit ability via Cores, Weapon Training, or other. Arcane Fluidity is good if you want to wear light armor).
- Tier 5 in AA: Maximum Corrosive Arrow damage, Soul Magic, Moon Bow,Force Arrows (for Force Damage when Acid won't work) and all Cores.
- Core 2 in PM: Zombie Shroud and Negative Energy Conduit.
- Core 2 in EK: Spellsword Acid (recommended) or other element, and Battle Mage for +3 Spellcraft.
Put the remaining AP into the ArchMage tree to increase your Spell Power (mainly Acid), Increase "Spell Critical: Elemental and Force," and reduce Maximize, Empower, and Extend costs. I also recommend selecting the Evocation Cores to get Magic Missile and Chain Missile.
Spell Theme: Focus on spells that don't have Saving Throws or Spell Resistance. This build lacks in Spell DC and Penetration.
Primary Spells: DOTs like Melf's Acid Arrow, Eladar's Electric Surge, Niac's Biting Cold, and Black Dragon Bolt. AOE/DOT spells, like Acid Fog, Cloud Kill, Ice Storm, and Incendiary Cloud. These spells take advantage of your Spell Power and Spell Critical, without worrying to much about DCs or Spell Pen.
Supporting Spells: Buffs like Jump, Expeditious Retreat, Night Shield, Shield, Greater Heroism, Blur/Displacement, Haste, Resist Energy, and Rage are all good for avoiding melee and damage while hitting targets with that bow. Solid Fog is decent for slowing down most trash, controlling the crowd a bit.
Of course, Death Aura, Lesser Death Aura, and Negative Energy Burst for healing.
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The principle theme of this build is to increase Spell Power to assist in getting the most damage out of the AA Corrosive Arrow and EK Elemental Arrow - Acid Enhancements. Supporting this, you will need to hit stuff with your bow, so increasing Ranged To-Hit is important. Backing up the damage from your bow are DOT and AOE/DOT spells, for which Spell Critical is also useful.
This build can easily get into Light Armor. Fitting into Medium Armor will come at a cost somewhere else.
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Play is a lot like Strimtom's Acid Arrow. Cast Solid Fog, Acid Fog, Cloud Kill, Ice Storm, and other AOE/DOTS over each other in a central area. Lure bad guys into this nightmarish cloud of doom and shoot them like fish in a barrel. You have three strategies going on at once, the AOE/DOT damage, your Acid Arrow damage, and some crowd control from the clouds. While you are [typically] focused on taking one bad guy out, the other bad guys are taking damage from the AOE/DOTS. Even if they are making their Saving Throws against a pathetic DC, most enemies will still be taking half damage while you're focused on your main target.
You can easily switch to power-kill mode by stacking some Max/Emp Dots on a Boss and hitting that ManyShots button. Be careful here since you will draw aggro unless your party's intimi-tank is a demigod.
Increasing Doubleshot is also important. Since most of your damage is coming from spell damage on the arrows, bonuses to critical hits aren't as useful as Spell Power; that is, don't take critical hit bonuses at the cost of Spell Power or To Hit bonuses.
You can stay in Zombie form quite a lot - maybe not in Running With the Devils, but most everywhere else. You should be running away, jumping around a lot, and using corners to your advantage. With some practice, you can dodge those killer light spells. The only other disadvantage of being in Zombie form is a few less spell points and -1 Spellpower from the -2 Intelligence.
Use Extended Death Auras to stay healed up, and don't forget those Inflict pots. You're pretty tough in zombie form with extra hit points and damage reduction. However, the best tactic is to keep out of melee, try to stay out of spell range, and get out of the way of any nasty ray spells.
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One cool feature of this build is that it uses surprisingly few Spell Points because it gets 20 temp spell points every 30 seconds and another 10 temp spell points almost constantly while you're shooting things. With an additional 12-15 Spell Points from Echos of Power, 42-45 Spell Points is achievable even when you would normally be out. That's enough for your buffs (one or two at a time), an Extended Death Aura, and many of your DOTs. In addition, your main source of damage is from your Corrosive and Acid Arrows, which don't use any spell points. Even without a shrine, you'll keep on going long after other casters don't have anything left. You may even find yourself passing up a lot of shrines.