In general, game effects originating from rules on individual cards supersede the rules in this rule book (that’s part of the fun!). However, there are a few rules that can’t be over-ridden by any game effect. Any game effect that would seem to break one of these rules is ignored.
1) THE RULE OF REPLACE THEN MODIFY
Whenever a combat value needs to be calculated for any game effect, the controller of the character whose value needs to be calculated starts with the printed value, applies all replacement values in any order, then applies the sum of all modifiers to arrive at a final result. Remember that a locked value will override any other replacement values and modifiers.
2) THE RULE OF THREE
Whenever the sum of all modifiers applied to a single combat value is greater than +3 or less than -3, the sum of all modifiers is instead +3 or -3, respectively. All modifiers continue to apply to the combat value; only their sum is changed. This rule only applies to modifiers, not to replacement values. Replacement values can alter the printed combat value by more than 3 before any modifiers apply, with modifiers still limited to a net modification of 3 on the replaced value.
3) THE RULE OF OCCUPANCY
Any game effect resulting in two or more characters occupying the same square, or characters, terrain markers, or objects occupying a square of blocking terrain, is prohibited (except for Debris markers, see Terrain, p. 12). If part of a game effect would cause this to happen, that part of the game effect is ignored. If moving or placing a character, terrain marker, or object would cause this, then the character, terrain markers, or object must instead move to or be placed in a different square. Characters using certain powers and abilities may freely travel through other characters and/or blocking terrain, but if it will end its movement in the same square as another character or blocking terrain, the moving character must end its movement before entering the occupied square.
4) THE RULE OF ACTION TOKENS
No game effect can result in more than 2 action tokens on a character. If part of a game effect would cause this to happen, that part of the game effect is ignored.
5) THE RULE OF MINIMUMS
If a game effect specifies that a combat value has a “minimum” value and the final result of calculating that value is less than the specified minimum, use that minimum value instead. If the final result is equal to or higher than the minimum value, use the final result normally. If the final result of calculating any combat value is less than zero, use zero instead. In both cases, all replacements and modifiers continue to apply; only the final result of the calculation is changed. If a locked value is less than a specified minimum or zero, use that minimum or zero instead.