Not sure why you took so to figure out that all the bosses would be magnified and you would have to magnify your abilities to match. Its Diablo's Hell levels all over again.
For that houserule, as it applies to the 3.5 era and Pathfinder Role Playing Game 1st edition: On a natural 20 or critical hit threat, if the roll and the attack modifiers are sufficient to hit the armor class of the target, apply full weapon damage plus all modifiers (STR mod, magic damage, etc.) Then roll again to "confirm", if it hits as well, then roll weapon damage as normal, adding only the STR or DEX (for those with the correct feats) modifiers, not magic or other modifiers. This applies to weapons with a "x2" crit modifier. For those with "x3", roll 2 confirmation rolls, and for "x4" weapons, roll 3 confirmations. If the original attack roll is a critical roll, and the total of that roll and would not be sufficient to hit the armor class of the target, roll weapon damage as though it were a normal hit, including magic modifiers. The reason for this is to precisely to avoid the repeated disappointment of landing critical hits and getting minimal damage. Addendum to the rule: If the "confirmation" roll is also a critical, it does maximum weapon damage plus the STR/Dex skill modifier and trigger another confirmation roll. If this third (bonus) roll is also a Critical, apply max weapon damage plus STR/DEX. If the target is still alive, it then rolls a Fortitude Save against the attacker's character level plus attack modifier plus any attack modifier on the weapon or is automatically knocked prone, disabled and at 0 hit points. Weapons of "x3" must land 2 "bonus" rolls as critical hits to trigger this Save and "x4" weapons must land 3 "bonus" rolls. The addendum seldom triggers for "x2' weapons and far less for "x3" and "x4" weapons. It does slow the roll of the dice, but makes for some really awesome super heroic stuff.
