nataliereed1984 wrote:Does anyone have the Mathhammer skills to fully hash this out, like the Primarchs duels on 1d4chan?
Just adding the
CP reroll in makes the mathhammer an order of magnitude more complex than it is in 7e, let alone whatever other stratagems you might add in, but I'll try.
In 30k (to illustrate the difference) I need to know that they're both
WS 7 so they'll both hit on 4+ on the first round but Guilliman will hit on 3+ on subsequent rounds because his
WS goes up over time in a challenge. Assuming neither charged Guilliman comes in with five attacks which could be S7/AP2 with Shred and Murderous Strike (Instant Death on a 6 to wound) at Initiative 6 or S10/AP1 at Initiative 1, while Abbadon has four Attacks at S8/AP2 that are Master-Crafted. Both have a 2+/4++ save, but Guilliman can reroll the first failed Invulnerable save each phase.
As Abbadon can't hit at AP2 before I1 there's no reason for Guilliman to use the Gladius rather than using the Hand of Dominion to guarantee he
IDs Abbadon, so it's (1/2) * (5/6) * (1/2) = 20.8% chance per attack of getting an Instant Death wound through per attack. The odds of getting at least one through are equal to one minus the odds of getting none through, so we flip it for a 79.2% chance of failing each time and raise that to the power of five for a 31.2% chance of failure on the first phase, flip that back again and we get a 68.8% chance of Abbadon dying in the first round. On subsequent rounds the odds of Abbadon dying increase as Guilliman starts to hit on 3+, up to about 80.4%. Abbadon gets between 0.78 and 0.83 damage in per turn depending whether his to-hit reroll and Guilliman's save reroll happen on the same attack or different attacks.
Combining Guilliman's It Will Not Die regen roll (5+ to regenerate a wound on his own turn) we can determine that on average Abbadon inflicts 1.6 wounds per game turn (two combat phases) and Guilliman regenerates 0.33 wounds in the same amount of time, so it'll take about 9.5 turns for Abbadon to kill Guilliman. The odds of Guilliman failing to get an
ID wound through on Abbadon in that time, given that his
WS resets to 7 every four rounds, are (0.3)^3*(0.2)^6, or about 0.0001728%, so I think I'm happy to conclude that Guilliman fighting Abbadon in 30k will always end with Guilliman's victory within at most two combat phases.
The problem with doing the same thing in
40k is factoring in the sheer number of things you need to reroll and the exponential effect this has on the amount of stuff you need to track, so this is going to take a while.
Guilliman's
CP rerolls are made a bit easier by his reroll auras; you're probably attacking with the sword rather than the Hand as Abbadon's Dark Destiny rule means he's taking 2 damage from either so the mortal wounds have a chance to make a difference, so you're almost rerolling all hit and wound rolls without
CP. I'm not going to write out all the math for this because we'd be here all day (there are 21 unique cases to consider with all the rerolls, even just taking an average of 2 for the extra mortal wounds), the long and short of it is that the expected value of Guilliman attacking Abbadon once is 1.134 damage. As Guilliman has six Attacks that's about 6.8 damage, which is close to enough to kill Abbadon but not quite. Going back to the calculation sheet getting the exact odds of actually killing Abbadon is a more complicated algorithm than I've dealt with before so while I might dig up some of my Python brute-forcing loops later I'll skip that step for now.
With Abbadon I'm going to operate under the assumption that the best thing to use the
CP reroll on is the Drach'nyen attacks; it'll make the computation a bit simpler. Assuming you reroll anything below a 4 (3.5 is the average of 1d6, it's closer to 3.33 when factoring in the fact that a 1 doesn't actually give you a bonus attack) that produces an 8.3% chance of taking a mortal wound and a 91.7% chance of getting an average of 4.2 extra attacks. Against Guilliman the extra
AP off the Talon doesn't help you, so your option is to wound on 4+ and deal flat 3 damage with Drach'nyen or wound on 3+ and deal d3 damage with the Talon; the flat damage is a bit better in practice, so we'll stick to that. With about ten attacks hitting on rerollable 2+ (97%), wounding on 4+ (50%), and getting past Guilliman's save 1/3 of the time that's about 16.2% of attacks getting through, dealing 3 damage per and making 10 of them Abbadon's going to get on average 4.85 damage through per turn.
So it looks like Abbadon needs about two turns of average rolls to kill Guilliman and Guilliman needs about two turns of average rolls to kill Abbadon, which means the win would go to whoever attacks first, but Guilliman's got more margin for error on his rolls (he deals 13 wounds in two turns and Abbadon's only got 8, while Abbadon deals 9.3 of Guilliman's 9 in two turns), and he stands back up after dying, so in practice Abbadon can't win the duel without a lot of help.
It also depends some on how the timing of "end of phase" works, with regards to when Guilliman stands back up and/or whose fight-again stratagem triggers first, but I'm too tired to go digging through
FAQs right now.