Odds of Succesful Stealth
Posted: Fri Feb 08, 2008 3:02 am
A thief, in a "typical" dungeon crawl, needs to hide & move silently in order to get into position for an ambush and backstab.
He is allowed to attempt it, at a movement penalty, with a -5 penalty to the roll.
Assuming DEX prime, a +2 DEX modifier, and a +2 bonus from something else (buffs, magic items, racial advantages, etc) our rogue has a 70% of passing each check before penalties. Let's assume it is a level appropriate foe for now, which cancels out the rogue's added level.
Now factor in a -5 penalty and the odds are only 45%.
45% x 45% = 20.25%
Thus our hapless rogue succeeds in setting up for a backstab only 1/5 of the time. If he must make a new pair of rolls each round he needs to move silently & hide to get into position, the odds drop even more rapidly.
Is this harsher than any other application of the SIEGE engine/skill system? Not only does it require two checks but it also is twice as hard to get bonuses (two different checks) and a -5 penalty is applied to boot.
It just seems quite punishing, especially compared to other editions (AD&D or 3.5).
He is allowed to attempt it, at a movement penalty, with a -5 penalty to the roll.
Assuming DEX prime, a +2 DEX modifier, and a +2 bonus from something else (buffs, magic items, racial advantages, etc) our rogue has a 70% of passing each check before penalties. Let's assume it is a level appropriate foe for now, which cancels out the rogue's added level.
Now factor in a -5 penalty and the odds are only 45%.
45% x 45% = 20.25%
Thus our hapless rogue succeeds in setting up for a backstab only 1/5 of the time. If he must make a new pair of rolls each round he needs to move silently & hide to get into position, the odds drop even more rapidly.
Is this harsher than any other application of the SIEGE engine/skill system? Not only does it require two checks but it also is twice as hard to get bonuses (two different checks) and a -5 penalty is applied to boot.
It just seems quite punishing, especially compared to other editions (AD&D or 3.5).