Hello...
Yesterday I was discussing with a friend about the rogue's weaknesses and ways to overcome them. We get to the point of what to do against a fighter with a heavy fortification adamantine armor (apart from waiting for him to take it out by himself). I looked at the PH and it states that you can't sunder a criature's armor. Then I thought about Shatter. The thing is, in a fair situation when both have 20th level equipment (let's say... both have for example, a cloak of resistance +6, a +5 tome, a +6 ability item, but not epic equipment or custom-made items), you don't have much chances to make the fighter fail the save.
So now I'm looking for ways to destroy/negate the fortification armor effect. Till now, all the ways I can think of are:
-Shatter
-Antimagic Field
-Dispell/Disjunction
-Energy missile/ray (in the case you play with the psionic/magic transparency)
I'm lookin, in order of interest, for: Combat tactic > Item > Feat > Spell > Prestige Class > 1-2 Class dip
Thanks for your attention