Rolemaster is by it's very nature a rather deadly rule system, up to the point where there are even some passages in the rule books mentioning this - alongside some advice for players to not neglect defensive stats and using some of their weapon-bonus for defence.
I think this is largely based in two important mechanics:
- Critical hits are deadly. In Rolemaster critical hits are rolled seperately from the attack roll, and they happen quite frequently. Though there are many different levels of critical hits (separated acc. to severeness and damage type), even the least severe ones can be deadly according to the rules - having at least some 1-3% chance of outright killing their target, with a 5-10% chance of de facto disabling the target for combat.
- Escalating penalties. In Rolemasters characters who took certain amounts of damage will get increasing penalties on essentially all their rolls, importantly including their combat rolls (attack/defence). Furthermore most of the critical hits will result in additional penalties - as a matter of fact this is really one of the main mechanics behind the critical hits.
Now, I can somehow deal with the extreme critical hit rolls by fudging them. Our group has always been doing that up to some degree, as we think spontaneous insta-kills just aren't a lot of fun - neither when happening to a PC years into a campaign, nor when happening to the BBEG in the final boss fight.
What gives me trouble are the escalating penalties: they have a sort of "the poor get poorer" effect, where already injured parties get penalties, which in turn lowers their defense, they are thus more likely to be injured further, thus getting even more penalties, etc. Often landing the first critical hit will essentially decide how combat will develop, or at least if an encounter is difficult/dangerous for the PCs or just a walk in the park.
I understand that this is a deliberate (and somewhat realistic) choice in the Rolemaster system, but IMHO it makes encounters rather hard to balance:
- Often what I thought would be a challenging fight is finished quickly after a player rolls a lucky crit, either outright killing his opponent or disabling them severely.
- Other times what should be a trivial skirmish suddenly takes a turn for the worse, when a PC suffers a steep critical hit that leaves them with almost none of their defence.
--> How can I as GM balance encounters where getting in a lucky hit has such a big effect on the course of combat?