Solo capability in DDO is much determined by build. And the Battle Cleric has been a favorite amongst players. The Battle Cleric is a Cleric that can do melee damage and take a beating. Clerics are good for soloing because of their healing skills and buffs and they fact that they can wear plate armor, all this makes them pretty durable. Giving them melee capabilities is done through giving them high STR and giving them melee feats ( Bastard Sword Khopesh Proficiency being the most important). The build below is a pure cleric build with high STR and Khopesh Proficiency but you can also multiclass a 1 or 2 levels into a melee class like fighter, rogue or monk if you want.
This build is made to solo fast and well all through the game, but feel free to modify it to your liking and playstyle. Getting 2 fighter levels might also be a good choice.
Level 20 Lawful Good Human Male (20 Cleric) Hit Points: 262 Spell Points: 1652 BAB: 15\15\20\25\25 Fortitude: 14 Reflex: 5 Will: 20
Abilities Base Stats Base Stats Modified Stats
(32 Point) (Level 1) (Level 20) (Level 20)
Strength 16 16 17
Dexterity 9 9 9
Constitution 14 14 14
Intelligence 10 10 10
Wisdom 17 22 26
Starting Ending Feat/Enhancement
Base Skills Base Skills Modified Skills
Skills (Level 1) (Level 20) (Level 20)
Balance 1 10 10