Roll: 20, hit - Multiply as normal critical
Roll: 20, 20, miss - Multiply as normal critical
Roll: 20, 20, hit - Multiply as normal, but add an additional 'critical multiplier' - 1 (ex: a 2x weapon would become a
2+13x, a 3x weapon would become a
3+25x, a 4x weapon would become a
4+37x
Roll: 20, 20, 20, miss - Multiply as normal, but add an additional 'critical multiplier' - 1 (ex: a 2x weapon would become a
2+13x, a 3x weapon would become a
3+25x, a 4x weapon would become a
4+37x
Roll: 20, 20, 20, hit - Multiply as normal, but add an additional 'critical multiplier' - (1 + 1 for each additional crit) (ex: a 2x weapon would become a
2+1+14x, a 3x weapon would become a
3+2+16x, a 4x weapon would become a
4+3+29x
There is always a minimum of +1 added for each additional confirmed critical, so once you are reduced to +1 you simply continue to add this.