The GURPS combat round now encompasses three seconds rather than the standard one second. This effects somewhat what can be accomplished in a given round. For long actions that normally require multiple rounds to accomplish, as a general rule of thumb, to figure out how many rounds these actions require now, divide the number of rounds required by 3, rounding up. I have revised the combat maneuvers to be somewhat simplified, combining Aim with Evaluate, and Move with Move & Attack. What can now be accomplished with the various combat maneuvers is listed in the table below.
Characters may spend a fatigue point to gain +2 to their Basic Speed for the purposes of initiative for that round.
Characters may spend a fatigue point to gain +2 to their Basic Move for one round.
Instead of shields giving a defense bonus to all active defenses, they instead only give their defense bonus to the Block defense. This prevents the abuse of simply taking shields for an increased bonus to Dodge (which unlike other defenses never goes down with use).
For every 2 points of margin of success a character has in her attack, the target's defense is lowered by 1. For example, say you have Attack-14. If you roll a 10, you succeed by 4, giving your target a -2 penalty to her defense. In the case of attacks with a high Rate of Fire (RoF), your target's defense is lowered by 1 for every 2 points on your margin of success past what is needed to score all your hits. For example, say you have Attack-18 on a weapon that is RoF 3 and Rcl 2. You roll a 10; your margin of success is 8. You needed a margin of 0 for one shot to be good enough to hit, a margin of 2 for two shots and a margin of 4 for 3 shots to be good enough to hit. Your margin of success was 4 above this, giving your target -2 to defense with the defense roll otherwise being resolved normally.
Instead of the normal penalties, characters suffer a -1 penalty to all skill, defense, IQ, DX, Will and Per rolls per 1/2 max HP lost. In addition, their basic move decreased by a number equal to the penalty. For example, a 10 HP character would suffer -1 at 5 HP, -2 at 0 HP, -3 at -5 HP, -4 at -10 HP, etc. At a -2 penalty the character is considered to be in moderate pain, severe pain at -4 and terrible pain at -6. (As per the rules for pain; B428). High Pain Threshold halves these penalties, rounded towards 0.
Penalties for fatigue accumulate similarly. Characters suffer -1 for every 1/2 max FP lost to all the rolls listed above, plus ST. The penalties for HP and FP do not stack, take whichever penalty is highest (in an absolute value sense).
Finally, ignore Knockback (B378) and Knockdown (B420), except in the case of specific attacks made for the purpose of their effects, as otherwise we are not using them.