Happyville Math
How movement speed and chance of hitting are actually worked out.
Movement Speed
Your base movement speed is 200 + 8*(speed skill). For example, if you speed skill is 3, then your base movement speed is 224. This is then modified based on what skills you are using:
Caution: Your movement speed is reduced by 33% while Caution is on.
Stealth: Your movement speed is reduced by [ 160 / (4 + stealth skill) ]% while using Stealth.
Observation: Your movement speed is reduced by [ 160 / (4 + observation skill) ]% while using Observation.
This table shows movement speed reduction for using Stealth or Observation for several skill amounts:
| Skill | Speed Penalty |
| 0 | -40% |
| 1 | -32% |
| 2 | -27% |
| 3 | -23% |
| 4 | -20% |
| 5 | -18% |
| 10 | -11% |
| 15 | -8% |
Combat
To decide whether an attack hits, first the game calculates an accuracy score for the attacker and an evasion score for the defender. The normal accuracy score is 5 + attack skill, but certain characters have special modifiers to this (for example, Insane get only 25% of their normal accuracy score).
The base evasion score is 5 + evasion skill, but this undergoes several modifiers.
First, if Caution is not turned on, the defender gets only 33% of the normal evasion score.
Then, there is a modifier based on the angle of the attack. An attack directly to the front multiplies the target's evasion score by 1.2 (a 20% increase), while an attack directly to the back multiplies it by 0.2 (an 80% decrease). Attacks at other angles yield multipliers somewhere between these two.
Certain characters also have bonuses or penalties to their evasion skill. For example, the Vampire has +100% armor bonus, so his evasion score is increased by 100%.
Once the accuracy and evasion scores are calculated, the game adds these and generates a random number between 0 and the total. If the random number comes out in the accuracy part of the range, the attack hits; if it comes out in the evasion part, the attack misses. Therefore, the chances of a hit are the same as the ratio of the accuracy score to the evasion score. If the accuracy and evasion are equal, there's equal chance of a hit or miss (1:1). If accuracy is twice evasion, then the odds are 2:1 in favor of a hit. Three times as much accuracy as evasion gives 3:1 odds in favor of a hit, and so forth. Neither probability ever becomes zero.
Here are some probabilities calculated out for your reference:
Chance to Hit from the Precise Front:
| Attack Skill (left) \ Evasion Skill (top) | 0 | 1 | 2 | 3 | 4 | 5 |
| 0 | 45% (72%) | 41% (68%) | 37% (64%) | 34% (61%) | 32% (58%) | 29% (55%) |
| 1 | 50% (75%) | 45% (72%) | 42% (68%) | 38% (65%) | 36% (63%) | 33% (60%) |
| 2 | 54% (78%) | 49% (75%) | 45% (72%) | 42% (69%) | 39% (66%) | 37% (64%) |
| 3 | 57% (80%) | 53% (77%) | 49% (74%) | 45% (72%) | 43% (69%) | 40% (67%) |
| 4 | 60% (82%) | 56% (79%) | 52% (76%) | 48% (74%) | 45% (72%) | 43% (69% |
| 5 | 63% (83%) | 58% (81%) | 54% (78%) | 51% (76%) | 48% (74%) | 45% (72%) |
Chance to Hit from the Precise Back:
| Attack Skill (left) \ Evasion Skill (top) | 0 | 1 | 2 | 3 | 4 | 5 |
| 0 | 83% (94%) | 81% (93%) | 78% (92%) | 76% (90%) | 74% (89%) | 71% (88%) |
| 1 | 86% (95%) | 83% (94%) | 81% (93%) | 79% (92%) | 77% (91%) | 75% (90%) |
| 2 | 88% (95%) | 85% (95%) | 83% (94%) | 81% (93%) | 80% (92%) | 91% (78%) |
| 3 | 89% (96%) | 87% (95%) | 85% (95%) | 83% (94%) | 82% (93%) | 80% (92%) |
| 4 | 90% (96%) | 88% (96%) | 87% (95%) | 85% (94%) | 83% (94%) | 82% (93%) |
| 5 | 91% (97%) | 89% (96%) | 88% (96%) | 86% (95%) | 85% (94%) | 83% (94%) |
Numbers in parentheses apply when the defender is not using Caution.