I've run Jonathan Blake's Lone Wolf Combat Success Probability Calculator for a few of (what I think) are the worst enemies.
As a note, I'm assuming each roll outcome (0-9) is equally probable, since at the time I wasn't using the random number table, but a D10. Applying the '2D gaussian' correction actually ups the odds of winning by around 1/3 for tough fights !
Results are "probability of winning / average EP remaining given victory", and Lone Wolf stats are from my last play-through, but may not be optimal.
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# Lone Wolf vs. Chaos-master (The Prisoners of Time: Section 204)
#
# First time reader with best initial scores and skills. Note that
# many directives are omitted since their default values are
# applicable.
Lone Wolf CS: 19
Lone Wolf CS Modifier: +1 CS (Lore-circle of Fire)
Lone Wolf CS Modifier: +3 CS (Lore-circle of Spirit)
Lone Wolf CS Modifier: +4 CS (Improved Weaponmastery / Sword)
Lone Wolf CS Modifier: +8 CS (Sommerswerd)
Lone Wolf CS Modifier: +2 CS (Shield)
Lone Wolf CS Modifier: +2 CS (Silver Helm)
Lone Wolf CS Modifier: +2 CS (This combat only : completed Lore-circle of Spirit)
Lone Wolf EP: 31
Lone Wolf EP Modifier: +2 EP (Lore-circle of Fire)
Lone Wolf EP Modifier: +3 EP (Lore-circle of Spirit)
Enemy CS: 47
Enemy EP: 68
Use Psi-surge: false
Psi-surge Bonus: 4 (since the Chaos-master is immune to Mindblast)
Psi-surge Penalty: 2
Psi-surge Cutoff: 6
Decision Mode: optimal
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without Psi-surge : 11.7% / 7.07EP
with Psi-surge : 16.9% / 6.23EP
boy am I glad I went for Circle of Spirit early on
As an aside, notice Lone Wolf base CS is 19. Assuming it is 'only' 18 (shift one column down on the combat result table), odds of victory become 0.50% and 2.81% (without or with Psi-surge).
Yeah, right.
If you swap the Ironheart Broadsword for the Sommerswerd, you get to fight a badly wounded Chaosmaster (40/58), with a 99% chance of success. However, the whole 'game balance' thing assumes that if you don't have the Summerswerd, you probably haven't played the series through, and thus don't have as many disciplines or as many nifty items. Without the Silver Helm and the Circle of Spirit, Lone Wolf loses 7CS on this fight, meaning even odds with the Summerswerd option.
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Lone Wolf CS: 19
Lone Wolf CS Modifier: +1 CS (Lore-circle of Fire)
Lone Wolf CS Modifier: +3 CS (Weaponmastery / Sword)
Lone Wolf CS Modifier: +8 CS (Sommerswerd)
Lone Wolf CS Modifier: +2 CS (Shield)
Lone Wolf CS Modifier: +2 CS (Silver Helm)
Lone Wolf CS Modifier: +2 CS (Potion of Alether)
Lone Wolf EP: 28
Lone Wolf EP Modifier: +2 EP (Lore-circle of Fire)
Enemy CS: 44
Enemy EP: 50
Use Psi-surge: false (immune to all)
Psi-surge Bonus: 4
Psi-surge Penalty: 2
Psi-surge Cutoff: 6
Decision Mode: optimal
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2.27% / 5.67EP. No way.
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Lone Wolf CS: 19
Lone Wolf CS Modifier: +1 CS (Lore-circle of Fire)
Lone Wolf CS Modifier: +3 CS (Lore-circle of Spirit)
Lone Wolf CS Modifier: +3 CS (Weaponmastery / Sword)
Lone Wolf CS Modifier: +8 CS (Sommerswerd)
Lone Wolf CS Modifier: +2 CS (Shield)
Lone Wolf CS Modifier: +2 CS (Silver Helm)
Lone Wolf EP: 28
Lone Wolf EP Modifier: +2 EP (Lore-circle of Fire)
Lone Wolf EP Modifier: +3 EP (Lore-circle of Spirit)
Enemy CS: 40
Enemy EP: 50
Use Psi-surge: false
Psi-surge Bonus: 4
Psi-surge Penalty: 2
Psi-surge Cutoff: 6
Decision Mode: optimal
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89.4% / 13.49 EP.
Odds of victory are pretty good. Lone Wolf isn't even too badly mauled ...
My worst fight ? Losing about 15EP against a Trapdoor (13/35) in the Kingdom of Terror. The Dakomyd at the end (a hefty 25/50) didn't manage to hurt me as much ...