ToME WikiKhymChanur: This proposal is different from New Trapping Ideas, this proposal doesn't add any new abilities, powers, or trapkits. I just think tha trapping could be useful as a skill if the equations used internally were modified.
Whether or not a monster disarms a trap is decided in two steps: first, if the monster even notices the trap, and, if the monster notices the trap, if the disarming succeeds. The probability of a monster NOT noticing the trap is: (150 - smartness + difficulty) / 300. Difficulty is equal to your trapping skill modified by the trapkit being well hidden or obvious; with trapping being an ability it's hard-coded to 25. Smartness is equal to the monster's level, increased by 10 if the monster has the "smart" flag, and increased by 20 if the monster has previously noted one of the player's traps.
Thus, when trapping was still a skill, if you used an ordinary (no-ego) trapkit against a level 1 monster, a trapping skill of 0 would mean a 1/2 chance of the monster not noticing the trap, while a skill of 50 would mean a 2/3 chance of of not being noticed by the monster. This means that, with a skill of 50, a level 1 monster still has a 1/3 chance of noticing the trap, which seems pretty ridiculous to me; another way of looking at it is that increasing the skill from 0 to 50 only increases the chance of non-detection by 1/3.
The same statistics apply for an ego trapkit with a hiddenness factor of 10: a 1/2 chance of the monster not noticing the trap at skill level 0, and a 2/3 chance of not noticing at skill level 50, for an increase of non-detection by just 1/3.
This is why nobody was using the trapping skill, because even getting it to skill level 50 didn't do that much good. So it was made into an ability that could be bought for 10 skill points, with the ability being hard-coded to skill level 25. However, this means that it's impossible to increase the skill level as you go deeper in the dungeon, so the traps start becomeing less effective. As NeilStevens noted on the "New Trapping Ideas" page, trapping is already powerful enough to kill Morgoth, but as Wastrel replied, it's not necessarily fun enough, since it resembles playing with a high spell failure rate of 75% or more. It was proposed that there be a second ability after the trapping ability, "Master Trapper", that would raise the skill level to 50, but for the two examples I give above, that would only increase the chance of non-detection by 14.3%.
So my proposal is to come up with a better formula for the propability of a trap being discovered (and perhaps a different formula for the probabilty of monster disarming failing). I'm currently not having any luck coming up with likely formulas, but perhaps someone else will have some good ideas.
NeilStevens: You're missing something: motivation. Do you know why I moved trapping to an ability? I did it because Rogues had too many skills they had to pump in order to get the full range of tricks, and I made trapping an ability so that people would become far more likely to use it.
Trapping was never meant to be a sole weapon, so it simply doesn't matter if trapping alone is boring.