[KotOR II] 2d6 added to Massive Criticals bonus with lightsabers?

[onderduiker 15]

Since the critical multiplier can be increased in the second game, I decided to investigate whether this would affect any Massive Criticals bonus. While Massive Criticals bonuses were added to, but not multiplied by, critical hits with ranged and melee weapons as expected, with lightsabers the bonus damage (as recorded in the Combat section of the Journal's Messages Log) was higher than expected, for both a main character and Kreia.

This wasn't a result of multiplication, since bonus damage added was still within the same range as a x2 critical with Perseverance (Shien) lightsaber form active or Power Attack (x3), or both (x4), and other than Power Attack there were no other sources of bonus damage (none on normal hits or without a Massive Criticals bonus). However, a lightsaber with a Discharge Energy Cell added 3-15 bonus damage rather than the expected 1-3, which is 2-12 more: although I didn't keep track of the distribution, values approaching minimum and maximum were much rarer, which suggested something more like a normal distribution with 1d3 and 2d6 (108 outcomes) rather than 1d3 and 1d12 (only 36 outcomes).

Tests with other Massive Criticals bonuses (Improved Discharge Energy Cell (1-6), Opila crystal (2-12) and black Name Crystal at level < 12 (1-4) and level > 32 (3-30)), albeit with much smaller sample sizes so far, also had bonus damage higher than expected, and didn't refute 2d6 being added. Can anyone confirm this is what's happening, and why it's happening? I know that these games are based somewhat on Neverwinter Nights, and a preliminary internet search suggests it may be something similar to overwhelming critical.

[onderduiker 15]

After further testing with a character using Master Critical Strike with a Keen Short Lightsaber (Nextor crystal), I'm now pretty sure Master Criticals: 2d6 (+2-12) is added to any lightsaber which already has a Massive Criticals bonus:

• Massive Criticals: 1d3 (+1-3) added bonus damage 3-15
• Massive Criticals: 1d4 (+1-4) added bonus damage 3-16
• Massive Criticals: 1d6 (+1-6) added bonus damage 3-18
• Massive Criticals: 1d8 (+1-8) added bonus damage 3-20
• Massive Criticals: 1d10 (+1-10) added bonus damage 3-22
• Massive Criticals: 1d12 (+1-12) added bonus damage 3-24

Combining a black Name Crystal focused at level < 12 (Massive Criticals: 1d4 (+1-4)) and a Discharge Energy Cell (Massive Criticals: 1d3 (+1-3)) added bonus damage 5-18, within the now expected range of 4-19 (the chance of 4 or 19 is 1/432 apiece), so I'm also pretty sure that this bonus is only added once, and not once for every Massive Criticals bonus.

As far as I can tell, the only prerequisites are using a lightsaber with a Massive Criticals bonus (any off hand (Short) Lightsaber must have its own bonus for this to be added to it as well): unlike Neverwinter Nights' overwhelming critical, level 21, Strength > 22, a Keen bonus (Improved Critical) and Power Attack aren't required.