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Published by Samuel Penn.

Also, see my profile for things that interest me.

Glendale Website - My main web site.

Yags - Main site for yet another game system, a generic GPL'd tabletop RPG.

Yagsbook - Documentation on the Yagsbook RPG documentation format, a Sourceforge project.

Mapcraft - Documentation on world mapping tools, another Sourceforge project.

Midnight Saga - An Ars Magica campaign.

Active Topics

The current topics are currently under active development (relatively speaking).

Yags is Another Game System - Game design notes for Yags, a Free roleplaying game system I use as the core system for most of my campaigns.

Yagsbook - Notes on an XML based documentation system I use for documenting Yags and related campaigns.

Full Thrust - Notes on Full Thrust

Stargrunt - Notes on Stargrunt.


Surprise and Tactics

Some notes on surprise in combat, and how it works. This is all a work in progress, brain storming to try and come up with a good way to solve the problem.


How will surprise work? A person who isn't in combat will be either:

  • Cautious
  • Alert
  • Unready
  • Relaxed


A Cautious person is expecting trouble, but doesn't necessarily know where (or who) the enemy are. They may be a guard investigating a disturbance or a SWAT officer clearing a house. The should be declaring actions on a round by round basis, and should have an initiative determined. Anyone in combat is considered to be Cautious.

The attacker makes a stealth check at the beginning of the round, against the target's awareness. If the target wins, then they know the attacker is there and can act. If the target has higher initiative (and is declaring second), then they will never be surprised.

The target may 'cover' an area, and declare to shoot/strike anything coming out (overwatch). On overwatch, the watcher has doubled initiative and is fast.

Surprise can also come from someone who wasn't visible at the start of the round. If they have lower initiative, then they must declare their action first, and so the target will not be surprised and can react to it. If the attacker has surprise on all the defenders, then any abilities to improve their initiative can be used for free.

If the hidden attacker had the advantage of initiative, then the target will have already declared before they know someone is there, so will be surprised.


An Alert person isn't expecting trouble, but is looking out for it. A guard standing watch near the beginning of their watch for example. An alert person isn't currently considered to be in combat.

When a group is making a surprise attack, then use one of the following when combat is declared:

  • The leader of the group makes an Intelligence x Tactics check.
  • The member with the lowest Agility x Stealth makes a stealth check.

The targets of the ambush each make a Perception x Awareness|Tactics check, against the difficulty determined by the ambush.

  • On a failure, the individual may not act or defend in the first round. In the following round, they get to determine initiative as if they had made a moderate success. They count as surprised.
  • On success, the individual makes an initiative roll, then halves the result. They do not count as surprised, but will be at a disadvantage throughout the combat. At any point they can spend a round to re-roll their initiative, in which case it won't be halved.
  • On a good success, roll initiative as normal, the individual wasn't at all surprised.


An unready person is not expecting any danger - in the middle of shopping or out for a gentle stroll for example.

Everything is done similar to an Alert target, except the target's check is halved.


A relaxed person is in no state to expect danger. They may be dozing, partying or totally engrossed in reading a book or playing a computer game. They get to fifth their roll when checking against the ambush. This pretty much means only a highly trained individual is going to be unsurprised by an ambush.

Simple Surprise

This is a simpler way at looking at the issue of surprise. First, some caveats.

  • There should not be a disadvantage to going first, if at all possible.
  • A slow person who has surprise should still get some benefit.
  • Initiative is simultaneous, just a way of measuring tactical advantage.

First, ignoring how to get surprise, what happens when you have surprise?

  • Decide on what you are going to do at normal initiative point.
  • Action is declared to those aware of you.
yags/surprise.txt · Last modified: 2015/02/04 22:40 (external edit)