I'm going to give a little background for my question and post first. If you want to skip this background stuff just scroll down to the asterisk lines.
I've run Rolemaster for over 20 years, off and on, and through several different versions. My favorite has always been the 2nd edition and with the reintroduction of Rolemaster Classic I can continue to play the version I fell in love with so long ago. Because I have played for so long I have taken from each version the parts that work for me and have an extensive House Rules for character creation and play.
Throughout all of this, regardless of the version played, I always seem to have issues with Perception, Stalk/Hide, Ambush, and Sense Ambush/Assassination. It never fails that during new character generation, especially with a new player, someone focuses on Stalk/Hide as a means of sneaking up on someone and doing what D&D coined as Backstab. Or they want to use Stalk/Hide as what I call a "Zero level Non-Magical Invisibility Spell". Somehow they think that if they have a high enough skill and roll a good enough ability, they can vanish, right before the eyes of everyone. Even throwing a smoke bomb to cover their escape like a ninja, which actually works. Usually it's a Thief, Rogue, or Assassin, sometimes a Night Blade, but in all it's the same. They generate real high stats during character creation (usually SD, AG, QU, IN, or RE) and through use of the various skill sets they are able to get ungodly high bonuses in any relevant skill they think will help them. I don't make it easier on myself, because I have imported, Adolescent Skill ranks, Everyman Skills, and Occupational Skills from newer systems, as well as some house modified rules to gain even more ability, into my game. I also allow one stat adjustment for 0 level to level 1. So any overpowered characters are of my own making. I don't have a problem with that. The way I look at it is these are the superheroes of their world, and I can actually ratchet up the danger level and know that my players can handle it even at lower levels.
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My problem has always been the lack of a definitive answer in regards to Stock and Hide vs. Perception. The rules books seem to almost always point to a successful Stock and Hide only being detectable by a successful Perception roll, with the penalty to perception being the amount the Stock and Hide was successful by plus any other modifications. Regardless of the edition this has only slightly changed. By itself this is OK, but leaves a lot of holes for players to drive whole herds of cattle through.
Characters, or NPC's/monsters for that matter, with very high Stalk/Hide ability are virtually invisible even when standing right in front of someone. Unless you compensate somehow with improved perception, or toss in modifiers that are only there to thwart this skill, it can become unbalanced very easily. Even in games that are low leveled and this skill is heavily regulated.
What I would like to know has anyone come up with a very reliable way to use Perception vs. Stalk/Hide, that seems to work universally?
Over the years I have read the books and compendiums, as well as many forums, and talked with other players, and GM's and as a result, I developed a means to help with this. It is by no means foolproof, but it does allow for detection of even these overpowered non-magical Stalk/Hide users. I didn't develop it, but have refined it over the years, and would like some input and suggestions as to how to make it better. It uses the Static Action chart and I will try to condense what I have in a word doc to just a few sentences and paragraphs. Please have a look and let me know what you think, what I may have missed, or what I got completely wrong, either through mis-understanding or through over complication.
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Stalk and Hide vs. Perception and Detect Ambush/Assassination
When trying to determine if someone is able to detect someone who is hiding or stalking, the difficulty is based upon a Static Maneuver roll.
Standard detection of something obvious is a Routine maneuver. What this means is, if someone is standing in the middle of an open area in normal light, and not attempting to hide, then detecting him with normal perception is Routine.
Stalking and Hiding Use:
Since normal perception is a Routine maneuver, any attempt to either Stalk or Hide will raise the detection level, even if unskilled.
When making any Stalk or Hide attempt the person attempting the skill, rolls their check. If the attempt just succeeds, then all perception checks will be made on the relevant maneuver level on the Static Action table set for their skill level.
If an attempt succeeds (101 +) by more than 20, then each multiple of 20 will raise the maneuver difficulty level by one. So that if a skilled attempt is made, and the total skill was 160, it would raise the detection attempt from a Light Maneuver to a Very Hard Maneuver.
• If an UM 100 is rolled during the Stalk/Hide check, then the Static Maneuver level will be raised one level per multiple of 10 successes. So a rolled skill of 160 that started with an UM 100 would go from a Light Maneuver to an Absurd Maneuver.
If at any time a Stalk or Hide fails, then the maneuver difficulty will decrease one level, then again another level per 20 failures, to a minimum of a Trivial maneuver. Essentially, if a perception roll is made to detect someone who failed to Stalk or Hide then it will most likely succeed.
• If the Stalk/Hide attempt fumbles, then the amount fumbled by will be added to the Perception detection attempt.
As can be seen, even if the Stalk/Hide attempt fails then it is not an automatic detection situation.
• Unskilled: For someone unskilled at Stalking or Hiding then perception will be attempted as an Easy maneuver.
• Skilled: For someone who is skilled at Stalking or Hiding then it raises the perception attempt to a Light maneuver.
• Apply any modifiers for the Static Action check to either the Stalk/Hide or Perception check as applicable.
• Optional: The Perception roll on the Static Action Maneuver table is modified by the either the bonus succeeded by over 100, or by the developed skill ranks of the one performing Stalk/Hide. So 5 ranks in Stalk/Hide would result in a -25 to the initial Perception roll. This is optional because the difficulty level of the check was already set by the Stalk/Hide attempt. So doing this would apply the same modifier twice.
• Optional: Ambush: The ranks in Ambush provide an additional modifier to the secondary roll if a complete success or failure Static Action is not resulted. So 5 ranks in Ambush would result in a -5 modifier to the second d100 roll. A successful Ambush roll is required to apply this modifier however.
Modifiers to the Perception roll vs. Stalk and Hide attempts:
Based upon the situation a person who attempts to make a Perception check will have the difficulty increased or decreased depending on when the perception would be made, or the circumstances surrounding the check.
• If the Stalk or Hide attempt occurs in an unlikely situation, the level of detection will increase one level. Situations that fit these criteria are being Stalked in a crowd, in one’s residence, or anywhere a Stalking/Hiding individual would not be expected under normal circumstances.
• If the Stalk or Hide attempt occurs in a likely situation, then the level of detection is unaffected.
• If the Stalk or Hide attempt occurs in a very likely situation or an attempt at Stalking/Hiding is expected, then the level of detection is reduced one level.
• If the situation is unlikely, likely, or very likely, and the one attempting to detect the Stalk/Hide, using Perception, has the Sense Ambush/Assassination skill, then the attempt will be decreased by one level.
• If the target of the Perception check was seen or detected prior, reduce the maneuver level by one.
• If there is no relevant means for the one attempting to Stalk/Hide to do so without being seen first or doing so, then the attempt level is lowered by two maneuver levels.
• Once the level of the Static Action has been determined the Perception roll is made applying all modifiers. If the attempt succeeds, then the target is detected. If failed, then the one attempting the Stalk/Hide may apply any modifier applicable to their next actions.
• New checks are not made unless the one Stalking/Hiding does something to trigger a new check, or they move inside a new detection range.
Range of Object/Target of Perception check:
Within 10’ …. +30
11’-30’ …. +20
31-100’ …. +10
101’-300’ …. +00
301’-500’ …. -10
501’-1000’ …. -20
1001’-3000’ …. -30
3001’-5000’ …. -50
5001’+ …. -70
Miscellaneous modifiers will only apply to the roll and not to the maneuver level, unless the modifier states otherwise.
See relevant Static Action Modifications Table for these and other modifying factors.