UMD: you need 24 to be able to cast scrolls with 0% failure (inc cha modifier)
SET Traps: is 15 for all traps except deadly gas (inc modifiers and take 20)
SEARCH: you can get away with very little in many campaigns, including OC. Searching against another PC who set traps means you need to max it out and even then it can be impossible.
LISTEN/SPOT: Listen is better than spot and allows you to 'see' through walls and possibly see invisible people ... apparently... Can't say it ever happened to me much *grin*. SPot works over a longer distance tho iirc sooooo . Wiki explains the search mechanics webshamen mentioned very well.
...and yip, ass as sin's need more skill points!
Have fun
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