“ 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”
“ The player characters, experienced and somewhat well known, hear rumors and travelers' tales about a distant area being overrun by dragons (or other terrifying monstrosities). The locals have sent them a message, begging for heroic aid.
When they investigate, they discover that nothing of the sort is going on. It turns out that a group of thieves wanted them out of the way so that they could rob them (or someone who would normally receive their protection).”
“ Go Beyonde
Wiz 1
For one full round, a gate to another dimension is opened. That Dimension is called Beyonde. It is a place of eldritch horrors but if you are careful, movement there for every 10 feet there you cover 1 mile here. It is very dangerous and creatures will attack). near instantaneously upon your arrival. in practice, you can roughly cover about 300 miles(after this point you will be subjected to overwhelming attack.Brave(Foolish?) peeps attempt to send armies through, that is very iffy. you can only get to approx. D^ miles of where you want to come out(requiring another casting of the spell.
Basically you have teleportation available to L 1 Wizard's , this would shake kingdoms to the core, if an enemy army could appear at any moment,D6 miles from a target. Warfare becomes very fluid and much smaller forces are scattered about the countryside.”