The Cat Test

“The Cat Test” is a test I devised for calibrating my game in homage to the infamous deadly house cat in AD&D. It's statted up in Monster Manual 2 with 1-5 hit points and can do a max of 5 hp damage per round! The test is what's the chance in combat of a starting fighter versus a house cat, and versus a tiger.

This has its origins in a fight in my game between a panther and a giant rat - the panther was wounded, and there was scepticism expressed about the giant rat's chances to survive in real life. Delta then had a post on the stats of different cats in AD&D, which prompted me to dream up this test to run on Explore to iron out the sizing rules.

The Fighter
First up is the fighter. Here's an average first level fighter:

Fighter Template
Skills: Melee: 3, Parry: 2, Athletics:2 (K1), Unarmed: 1, Thrown: 1, Survival: 14.
Arms & Armour: Sword (P2 A2 K2) Shield (P3) Chain [4] Steel Helm [2].
Combat: Melee: P17 A5 K3 [8/11/14/17 (20)]
FR39 XP44

The first line is the skills, the second is what arms and armour they've got, the third is the combat bonuses (just from adding up items on the first two lines, e.g. Melee 3 & A2 from sword give Melee A5) The last line is the fight rating and XP you gain if you kill it.

I've called it a template as from these stats you can quickly determine the stats for a fighter of any level, or any size (e.g. a giant fighter); also template seems appropriate as a fighter is just one particular choice of skills, you can make up your own templates.

Adding levels: Each level you get +1 on all skills you are trained in, and +1 on survival (which is not actually a skill). Which means the fighter gets +1 parry, +1 attack, +0.5 kill, +1 survival every level. So @3rd level they'd be Melee: P19 A7 K4 [8/12/15/19 (22)].

"Level" here is slightly misleading; you improve your skills incrementally as you gain XP - it's only saves that improve when you gain enough XP to make the next level. The Fighter template is just a predefined way of spending that XP on skills. 

Changing Size: Size is included in calculating combat stats; the effect of increasing it is to give a bonus on kill and all your saves (where +4 size is double the weight). So size +2 would make you Melee: P17 A5 K5 [10/13/16/19 (22)].

Note that changing size doesn't give you any attack or parry bonuses. On the one hand being smaller makes you harder to hit because you're a smaller target, but on the other hand being bigger makes it more difficult to get past your defences and land a blow. By matching increases in kill with increases in saves, changing the size of both combatants has absolutely no effect on the fight. Two giants fighting is the same as two humans fighting.

Being larger does make you easier to hit for missile attacks, but only in that it reduces the range penalty.

I've described the Fight Rating (FR) before - it's attack + parry + kill + the middle save. It's a measure of how good at fighting you are. Your rating increases by 3 every +1 level, by 2 every +1 size. From this you lookup how many XP defeating it earns you (it doubles every +6 FR). From this you can easily approximate how well two combatants will fare in a fight by comparing the ratios of their XP squared.

The Tiger
I'm going to assume a man sized tiger would fight about as well as a fighter, and claws and teeth and dodging being as good as sword (P2 A2 K2) & dagger (P1 A1 K1), with a tough hide giving the same as full leather [4].

Skills: Melee: 3, Parry: 2, Athletics:2 (K1), Survival: 14+7.
Arms & Armour: Sword & Dagger (P3 A3 K3) Full leather [4].
Melee: P15 A6 K:4. [6/9/12/15 (18)].
FR37 XP36

 So from this we get the stats for a Tiger by sizing it up:

Tiger: Size 7 (600lb), Height -8 (3'6''), Length 8 (10')
Melee: P15 A6 K:11. [13/16/19/22 (25)].
FR51 XP180

The Pussycat
I originally had the domestic cat as a down-sized tiger, but while the lion has prey up to twice its size, the prey of a domestic cat is much smaller than itself, so I've reduced its kill by 3:

Domestic Cat: Size -16 (10lb), Height -28 (10''), Length -20 (18'')
Melee: P15 A6 K-15. [-10/-7/-4/-1 (2)].
FR2 XP1

That's the stats for a tiger, but -23 size, -23 saves, -26 kill.

Cat vs Fighter
So here's the answer you've all been waiting for...

Domestic Cat (1XP) vs 1st level Fighter (44XP): 1:1936.
Tiger (180XP) vs 1st level Fighter (44XP): 17:1.

These are only a ballpark figure and it gets less accurate the more extreme the comparisons so I ran it through my combat simulator which comes up with accurate odds: 1:700 for the domestic cat, 12:1 for the tiger.

The Tiger seems about right, and is quite deadly.

I think the pussycat's chances are still massively overrated, but I'm glad that it's in the right ballpark. In reality it would turn and flee rather than engage in a fight, but what if it is demonically possessed? You could add rules such as it always loses initiative the first round (long weapon advantage), or other rules for a small creature against a large one, but fundamentally it has a chance to kill PCs as a consequence of allowing PCs to have a chance to slay a giant.

Another day I'll talk about how to make interesting differences between the big cats.