Niten has both the scaling bonuses from perception (at 12 it’s a total of 24 damage) and flowing water, which doubles damage on non-crit (at the cost of almost-doubling move cost).
Melee doesn’t directly buff damage.
Strength does, but only bashing and the effect isn’t huge. On average, it’s str/4+(str-9)/2+(str-20)*1.5 dropping the negative ones. At 16 str, it wouldn’t go above 11, before scaling.
So a flowing water hit by a 12 per character with a katana would be (4+38+12+12)*2=132 without any strength bonuses and skill scaling.
With str 16 and a good hit, it would be: (4+11+38+12+12)*2 = 154
At 7 skill, bashing and cutting both get 20% boost to damage. So 185 damage.
Alternatively, we could get a crit and get a fire+stone cut, for 150% damage, but also a crit boost.
In this case damage would be (this time separately bashing/cutting):
Bashing: (4+11+8+12)1.21.51.5 = 84
Cutting: (38+12)1.21.61.5 = 144
Total: 63+96=228
Scientist has 80 hp. Corpse damage is 5*(overflow/2/maxhp). If overflow>150 and corpse damage>5, gib. Overflow is a float and so not lost to fractions.
A 228 hit has 148 overflow and 4.6 corpse damage. Shouldn’t gib, but if the zed is damaged, it easily can gib.
A 241 hit would have 161 overflow, 5.03 corpse damage and thus would gib a full hp scientist.