“ The characters are wandering through the bustling crowds of Lasopolis. A street conjuror is performing a simple summoning spell, something for the kiddies. A bit of odious purple powder in the fire, an incantation and out pops a saak-lizard or a muhmentarsh, writhing from the flaming brazier. But the conjuror has only a poor grasp of the arcane magical tongue. A few stuttered syllables could lead to Other Things coming through the brazier and giving the crowd more entertainment than they had paid for...”
“ As you travel through the thick growth of a forest, a great shadow suddenly moves over you. You raise your head fast, but whatever it was, it was faster. However you try, you don't see anything, and nothing approaches you. Maybe it is better so.”
“ 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”