Table 6A: General Difficulty modifiers
Chances of success are	Opponent's views are	Difficulty modifier
Virtually nil	Opposite	+3
Almost impossible	Largely opposite	+2
Unlikely	Partly opposite	+1
Evens	Neutral	0
Likely	Slightly similar	-1
Almost certain	Largely similar	-2
A certainty	In accord	-3

Table 6B: Combat situation modifiers
Combat situation	Difficulty modifier
Attacker surprises opponent or takes opponent unawares	-2
Attacker cannot see	+3
Attacker partly blinded	+1
Fog or moonlit night	+1 an area
Night	+2 an area
Attacker stunned* or disoriented	+1
Underwater, unless this is creature's natural environment	+1
Gun with telescopic or laser sights	-1 every two complete areas**
* See Appendix 2
** Sights in effect reduce the difficulty due to range
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