Highest Possible Warforged DR chart.
1st: 3DR (2 Adamantite Body / 1 Enhancement)
3rd: 4DR (2 Adamantite Body / 1 Enhancement / 1 Feat)
6th: 6DR (2 Adamantite Body / 2 Enhancements / 2 Feats)
9th: 7DR (2 Adamantite Body / 2 Enhancements / 3 Feats)
11th: 8DR (2 Adamantite Body / 3 Enhancements / 3 Feats)
12th: 9DR (2 Adamantite Body / 3 Enhancements / 4 Feats)
15th: 10DR (2 Adamantite Body / 3 Enhancements / 5 Feats)
18th: 11DR (2 Adamantite Body / 3 Enhancements / 6 Feats)
NOTES:
- As a general rule, the only DR that stacks is passive and active. (e.g. Blocking DR + Highest Passive DR)
Blocking DR is the listed Shield DR + half your BAB.- The Warforged Improved Damage Resistance Feat cannot be purchased with Fighter Bonus Feats.
- Barbarian DR does not stack with Warforged DR.
- A pure Warforged Favored Soul gets an additional 10DR/Adamantite at 20th level that will stack with Warforged DR.
(Pure FvS fleshies just get 10DR/Silver at 20th level.)- The Docent of Defiance 20DR proc doesn't stack with Adamantite DR.
The 20/- is listed on a separate line from adamantite.
P.S. Don't gimp yourself and actually do this. I just wanted to know the maximums and thought I'd post it for posterity. Please let me know if I should make any corrections.