how did you beat the final secret boss?
Spoiler (click to show/hide)
i keep asphyxiating in space
Well, it's basically just grinding stats until you're good enough. But I did the math, so for the specifics, see the spoiler:
Spoiler (click to show/hide)
Basically, this guy has 4000 health, and deals linearly scaling damage to you. Assuming you attack as fast as you can, you'll take 4 hits of asphyxiation damage while you're attacking, and then he'll up the amount of damage per hit by 1, and then you'll take another 4-5 hits before you can attack again. Looking at it another way, you'll take 4 1-damage hits before your first attack, and then it's just multiples of ~8.5 from then on. So this isn't 100% accurate, but as a result, we can model his damage output as an arithmetic series: 4*1 + 8.5*2 + 8.5*3 + 8.5*4 + ... + 8.5*X, where X is the number turns you fight.
Thus, we have:
f(X) = 4*1 + 8.5*1 - 8.5*1 + 8.5*2 + 8.5*3 + 8.5*4 + ... + 8.5*X
f(X) = 8.5*(1 + 2 + ... + X) + 4 - 8.5*1
f(X) = 8.5*(1 + 2 + ... + X) - 4.5
f(X) = 8.5*( X*(X+1)/2 ) - 4.5
f(X) = 4.25*X^2 + 4.25*X - 4.5
However, though that is the damage dealt by the end of your Xth attack for most of the fight, your final attack will be instantaneous due to a glitch(?) where no animation is played for the finishing blow in a fight. Thus, a more accurate formula will need to give us the damage you take before your Xth attack. As ~4 hits are dealt to you during your attack animation, you can simply subtract 4*X from f(X) to get:
f(x) = 4.25*X^2 + 0.25*X - 4.5
Using this formula, we can calculate the rough amount of charisma you'll need to survive long enough to make the Xth attack in this fight:
First number is the amount of turns, the second number is the amount of damage you'll take before your attack. These numbers are fairly accurate. I tested it only once because it takes a while, but after 15 turns, I had taken precisely 951 damage. However, numbers may vary based on the rapidity with which you attack; if you are slow to click, you will take more damage.
Now, you really don't need more than 1000 Cha, so you should be able to end the fight in less than 15 turns. In order to do this, you need to deal 4000 damage in the number of turns which corresponds to your charisma - though it's always better to be safer, so try to get more Cha and Str/Int than is necessary. I personally advise Str, as it deals more damage per point invested and gives you extra stamina at around 35 and 70 str, which increases the amount of stat points you can gain per day. However, requirements for both are listed, given X turns, and assuming that the damage dealt is roughly equivalent to 1.5*Str or 1*Int.
1: 2667 4000
2: 1334 2000
3: 889 1334
4: 667 1000
5: 534 800
6: 445 667
7: 381 572
8: 334 500
9: 297 445
10: 267 400
11: 243 364
12: 223 334
13: 206 308
14: 191 286
15: 178 267
First number is the number of attacks you need to kill with a given Str/Int stat, second number is the Str stat, last number is the Int stat. These numbers are also fairly accurate, though you may actually require less Str/Int to win in X turns than listed, since you appear to deal slightly more damage than 1.5*Str or 1*Int once you've raised them high enough - though I'm less sure of that.
Lastly, I advise to try to go a couple levels higher in both for the stats you shoot for. For example, if you want to win in 10 turns, make sure you can survive for 11 (500 Cha) but kill in 9 (300 Str or 450 Int). So long as you can get your stats to around that threshold, you'll do fine.