“ Rather than making a baddy impossible to hit, consider giving it mega-hit points.
Super hard to hit leads to great player frustration. Allowing them to do damage leads to a sense of accomplishment. another variation of this would be to give the bad guy a forcefield that shows damage.You could also give them a mastermind ability that sluffs the damage of to minions who should be easy to kill.Once in a while a super high to hit encounter is ok ,but it should be few and far between.
Your mileage may vary”
“ I've never been happy that almost every player picks long sword and greatsword, so I made a special chart to make them more unique. I use this in OSR and Pathfinder. I use 20 only as crit threat(Pathfinder speak),double damage.
dagger +2 to hit, D4 damage
short sword +1 to hit, d6 damage
long sword, threatens critical(see below) on 19-20, D8 damage
battle axe, ignores one Damage resistance( some monsters have resistance to damage in the form of knocks damage off before you do actual damage)(scale at higher L?) D8 damage
Mace, 0ne damage on a miss(Scalable?) D8 damage (Ok , should prob only be vrs Metal armor but not looking for that kind of complexity)
spear D6 damage, d12 damage vrs large creatures
great sword 2d6 damage
military pick d6 damage, x3 damage( triple dice damage) on crit(20)
great axe D10 damage, +3 to confirm crit ( in pathfinder if you roll a 20 you then reroll your attack and if you hit the targets AC, you get a critical multiplier)
quarterstaff(2 handed) D6 damage +1 bonus to AC (to the better)
Etc.”
“ Woodrats - In a fantasy realm of cooshee (elven dogs/cats) it is to be expected that there is some sort of elven vermin. These mercurial rats are lightning quick, and are capable of hiding in plain sight. Other than this, they have no special ability.”