Stealth as Combat

Stealth is one of those mechanics I never felt was right in TTRPGs. Often, you have games where the character that is the worst in stealth is the one deciding the fate of the party, as the least sneaky person has to be the one to make the roll that counts. Beyond that minor gripe, you also have the issue that unlike most rolls, Stealth totally changes the game in a single roll. It would be a bit like deciding all of combat on a single roll; the consequences are too dire for one roll. Getting found out doesn't instantly mean the enemy has “raised an alarm”, nor does it mean you have failed your “mission” but it does typically mean you can't enter stealth again until at least one group of enemies is eliminated AND it creates a pretty bad situation. Plus the actual negatives for failing a stealth roll often outweigh the positives; stealing a single item or sneaking past a guard to avoid one fight may not be worth the trouble of splitting up the party, putting out a torch, getting caught flatfooted, etc.

Now of course all of the above depends very heavily on the game. Here's an idea on how to do stealth in a semi-generic fantasy dungeon crawler.

Stealth Roll Roughdraft

This is a basic starting point for sneaking rolls; Stealth rolls are d20 + Stealth bonus (Rogue) + Dexterity modifier.

For intelligent humanoid enemies, roll over their morale.

For unintelligent animal or monster enemies, roll under their morale and add your bonuses to the target number instead of the die roll.

Intelligent enemies who have high morale are most likely going to be putting out watches, be more focused, and be more dedicated to their tasks. It's much easier to sneak by the dumb goblins gambling around a fire with low morale then sneaking past the King's high royal guard with very high morale. Unintelligent beasts, on the other hand, are more likely to be flighty and prey animals on constant vigil are more likely to notice you quickly. If you're playing a game that doesn't already use stealth DCs or target numbers, then this is a shortcut.

For creatures that do not have morale, you either always succeed in sneaking past them (undead), or always fail (constructs). You can still be “found” by them though if you perform an action or if a noise is activated, this simply simulates the idea of being able to get the jump on a zombie before it notices you since it's slow and stupid, not avoiding its sniffing ability to smell the living.

If a monster already has a X in chance to be surprised, add that chance to be surprised as a +2 bonus to your stealth roll, or a -2 negative if they're very unlikely to be surprised. For enemies who are never surprised, you can't sneak past them.

Stealth as Combat

Whenever you want to sneak up on someone and perform one of several special actions, you need to make a stealth rolls. Some types of armor make sneaking more difficult, or downright impossible. You only roll to perform actions on the state that you are in, where as the lower states are free actions with no chance of being discovered.

 

Every time you fail a stealth roll, you are closer to being discovered. Move down a state.

If you fail a first roll in the Stealth state- you are now in the Caution state, and cannot attempt actions exclusive to the first state. If you are performing an action on a lower State, you do not need to roll- this means that in the Stealth state, you can always perform a ranged sneak attack without a roll, or in the Alerted state, you can attempt to disengage without alerting the enemy to your presence- but it would require a roll, and failure would cause you to be discovered. You can't try to attempt to stealthily pop out and shoot your bow as a surprise attack in the Alerted state, because the enemies are already scanning the treeline, and so on.

You always begin on the Stealth state if you are approaching the enemy from behind, in darkness, or they otherwise have no idea you are approaching. If the guards had a tip off that somebody might try to break into the palace on the night of the ball; then sorry, you start stealth in the Caution state instead. You could think of a combat encounter or reaction check as being the 4th and final, lowest state if you drop from Alerted, meaning even if the guards yell "who goes there?" but you succeed your check to sneak away, you don't have to interact with them anymore.

Stealth State-

The enemy has no idea you are coming towards them, and with proper footwork you can get within touching distance of the enemy. Your roll to stealth is to get close enough to them to perform one of these acitons. You can perform any action in a lower state without needing a roll, as the enemy has no clue as to where you are and there is no chance of being alerted.

• Make a melee sneak attack/coup de grace on an opponent with a dagger or other small weapon.
• Perform a silent nonlethal takedown, if you know how.
• Grab an enemy and hold them hostage. (Requires grappling/enemy gets a save)
• Steal an item off their person.
• Pass by the Enemy unnoticed through a entrance they are guarding.

Caution State-

Either due to happenstance, the enemy is now either looking in your direction, is slightly on edge, or is otherwise put in a position where getting close to them is now impossible. You can no longer perform any close up actions as in the first state, but can perform any of these actions with a successful stealth roll. You will start in this state for enemies who are on watch, with their backs to a wall or ally, or in a well lit area.

• Perform a ranged sneak attack. If your attack kills the enemy, they cannot make noise in time to alert their allies unless the noise from the attack is enough (explosive arrow)
• Steal an object from the room or general area without being noticed.
• Throw a stone or otherwise make a distraction to shift the enemy's focus. (Doing this will allow you to move temporarily into the first state, or draw their attention so you can pass)
• Pass by the Enemy unnoticed through an entrance they are patrolling.

Alerted State-

In this state, the enemy is aware that someone is there and will not be taken by surprise. You cannot get out in the open long enough to make a ranged attack, or get close enough to make a close range attack without them being alerted and rolling for initiative as normal. This state is entered as the default if the enemy is actively looking for intruders, and coming towards your hiding place.

• Disengage (move out of the contested area)
• Wait out the enemy (Moves you up one state, takes 1 exploration turn)
• Draw your weapon (roll initiative without being surprised)
• Use an item or silent spell without getting caught

If you fail a Stealth roll in the alerted state, or initiate combat, openly through killing a foe with their fellows nearby, then combat beings and initiative is rolled. Enemies surprised have a 1 in 6 chance of acting on the first round (surprise round).

Note that how the options are ordered; you can wait out the enemy without a roll in all states unless alerted, since they have a chance to find you. You can always move away from an encounter if they aren't looking for you, and only the most stealthy character has to roll to do anything in this system. Everyone else can either disengage, lock their bolts and fire in a surprise round, and so on without needing a roll.

Note; Guarding is for entrances or portals that enemies are directly standing besides or in front of. Such as the classic two guards posted out the entrance of a gate. Slipping by them would require quite a lot of stealth. Patrolling instead refers to entrances the a guard is only occasionally watching or passing by, such as a window in the first floor of a palace.