Minimum Disable Device skill rank required: 16
It uses the raw skill rank only, and does not take into account any skill buffs or ability bonuses.
To figure this out, I opened up the NWN 2 campaign in the toolset editor, and tracked down the conversation script for the tithe box.
Click the image to open in the entire window. You may have to click on the image again to zoom in.
Key Points from the Script
gc_skill_rank(19,15) Player can detect the trap if they have a Search skill of 15.
gc_skill_rank(7,16) Player can disarm the trap if they have a Disable Device skill of 16.
gc_skill_rank(int nSkill, int nRank)
Determine if PC Speaker has sufficient rank in a particular skill.
int nSkill = skill int to check (19 == Search, 7 == Disable Device)
int nRank = minimum rank to return TRUE
gc_skill_rank checks for raw skill ranks only; It does not consider skill buffs or ability bonuses.
Assuming the Player has both a Search skill rank of 15, and a Disable Device skill rank of 16, they will be able to find the trap and disarm it. There are no other conditions in the script that would prevent robbing from the church box.
Achieving the Required Skill Level
Class Skills: (Character Level + 3)
Cross-Class Skills: (Character Level + 3) / 2 [rounded down]
Four classes have Disable Device as a Class Skill: Rogue, Arcane Trickster, Assassin, Shadow Thief. Your skill cap will stay at Class Skill level as long as you have at least 1 level of one of these classes, even if your current class is different.
So, in order to get your Disable Device skill rank up to 16, you need one to do one of the following:
- Be at least character level 13, and one of your classes has to be a Rogue, Arcane Trickster, Assassin, or Shadow Thief of Amn.
- Be at least character level 29.