Shameless self-quote:
According to vanilla D&D rules, if you were running while invisible, you would not get a static 1 or 5 for your rolls. You'd get a 5+1d20-20. The most you'd get out of such a roll is 5, and you get that guaranteed on Sundren.
Now, if you were to activate your sneak mode, then you would get 5+1d20 on your rolls, with no penalty. Of course the downside is that you move a lot slower.
official D&D rules state that on making a move silently check while running and invisible, you get a -20 penalty (opposed to their Listen). Sundren's implementation lets you take 20 to compensate for low MS skill values.
Now, if you were to activate your sneak mode, then you would get 5+1d20 on your rolls, with no penalty. Of course the downside is that you move a lot slower.


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