There are four basic outcomes from a Surprise Roll:
- Neither the PCs or the “monster(s)” are surprised
- The PCs are surprised.
- The “monster(s)” are surprised
- Both the PCs and the “monster(s)” are surprised
This leaves room for four different kinds of encounters every time a random encounter is rolled up inside a city. It also suggests four different kinds of information that can be conveyed to either the players or the Referee:
Neither the PCs or the “monster(s)” are surprisedThis is a routine encounter where the group or individual encountered is doing something mundane. The PCs become aware of the existence of this group or individual and get the physical description of that group or individual that they are cultivating for public consumption (if they are in disguise, the PCs get a description of the disguise with no hint that it is a disguise).
The PCs are surprised.This is a new bit of information for the Referee. The group or individual encountered is actively hunting the PCs. The word “hunting” can mean something different depending on which group or individual is doing the hunting. In some cases it may mean spying, in others it may mean recruiting or being pressed into service, in others it may mean an audience with the leader of said group or it could simply mean that the PCs have a group or individual that has decided that they need to be killed off.
The “monster(s)” are surprisedThis is a situation where the PCs encounter the group or individual doing something with their public face off. They might catch the Thieves’ Guild during a heist, a mercenary group escorting a person of interest to a secret meeting, get a glimpse of a monster underneath a mask, the Mage Guild and its allies the Nameless kidnapping an adventurer, etc.
Both the PCs and the “monster(s)” are surprisedThis is a combination of the previous two encounters. Rather than just seeing the nefarious/secret goings on, the PCs become aware that they are the target of said activity.
Using this system, of course, requires either an ability to improvise on the part of the Referee or some prep time where each group/individual on an encounter table is detailed out to include what exactly each type of encounter is going to look like.
Personally, I prefer a more improvisational approach because it allows me to be surprised as a Referee in much the same way my players get to experience surprise. It also allows me to tailor such encounters to the needs of the campaign as it unfolds. For example, players tend to bring various NPCs into their fold. Including these NPCs into a surprise encounter can bring a level of depth to a campaign that wouldn’t be possible by pre-planning every encounter, especially if that NPC is perceived to have betrayed the party.