I created and tested this build as a level 40 build with no magic items in the character training module with a +20 monster powerup, and it did OK. My guess is that it's not totally unplayable PvM, but I haven't tested that yet. If you do decide to play it, watch out for the alignment shift at level 20. Other than that it's a great build. I'd like to thank Thax, The Supreme Force, FinneousPJ (although he only joined in the end), onion eater and even avado (yes, I forgive you )* for the advice that helped me improve it. This build was originally inspired in Sir Smokesalot by Midthrates, which is now illegal in the last patch. Here's the final version!
* I apologize if I forgot to mention anyone. Thanks to you as well!
THE FORSAKEN HOLY DRAGON
Paladin (20) / Druid (18) / Monk (2)
RACE: Human
ALIGNMENT: Lawful Good -> Lawful Neutral (at level 20)
STARTING STATS:
STR - 14 (+2) DEX - 8 (-1) CON - 10 (0) WIS - 16 (+3) INT - 14 (+2) CHA - 14 (+2)
ENDING STATS:
STR - 14 (+4) DEX - 8 (-1) CON - 10 (0) WIS - 30 (10) INT - 14 (+2) CHA - 16 (+3)
BASIC STATS:
Hit Points: 360
Skillpoints: 255
Saving Throws: (Fort/Ref/Will): 25/18/29 (+8 vs Spells, Evasion)
AC: (naked): 27
BAB: 30
AB (naked/unbuffed): 32
Buffed AB: 51 (with a mundane scimitar)
Spellcasting: Paladin (20), Druid (18).
LEVELING GUIDE:
1- Paladin - Power Attack, Knockdown 2- Paladin 3- Paladin - Divine Shield 4- Paladin - WIS +1 (17) 5- Paladin 6- Paladin - Divine Might 7- Paladin 8- Paladin - WIS +1 (18) 9- Paladin - Extend Spell 10- Paladin 11- Paladin 12- Paladin - Improved Knockdown, WIS +1 (19) 13- Paladin 14- Paladin 15- Paladin - Empower Spell 16- Paladin - WIS +1 (20) 17- Paladin 18- Paladin - Improved Critical (Unarmed Strike) 19- Paladin 20- Paladin - WIS +1 (21) 21- Druid - Great Wisdom I (22) 22- Druid 23- Druid 24- Druid - Great Wisdom II (23), WIS +1 (24) 25- Druid 26- Druid 27- Druid - Great Wisdom III (25) 28- Druid - WIS +1 (26) 29- Druid 30- Druid - Great Wisdom IV (27) 31- Druid - 32- Druid - WIS +1 (28) 33- Druid - Great Wisdom V (29) 34- Druid - 35- Druid 36- Druid - Great Wisdom VI (30), CHA +1 (15) 37- Druid 38- Monk 39- Druid - Dragon Shape 40- Monk - CHA +1 (16)
)* for the advice that helped me improve it. This build was originally inspired in Sir Smokesalot by Midthrates, which is now illegal in the last patch. Here's the final version! 
