I have played around with various combat rules options here on my blog, but ultimately my Tuesday night play group which has now been playing Five by Five for some months has settled into the simplest interpretations of combat and have taken to hand-waving the importance of things like weapons and armor.
This is our Five by Five.
To create a character choose five traits that you make up specifically for your character like: Astronaut, Race Car Driver, Martial Artist, Detective, Gypsy, Computer Hacker, Mountain Climber ... whatever.
Rate these five traits from 1 to 5 with 5 being the best and 1 the worst (the one with the least amount of skill behind it.) Now, add +1 to each of these ratings. This new number is your starting score in each trait.
Now pick one thing that you have trouble with. Call this your Trouble trait. When called upon to "avoid trouble" related to your trouble trait you must roll Doubles to succeed. The Trouble Trait is a weakness or difficulty for your character.
For all Traits except your Trouble Trait, roll your score or less on a 5x5 roll to succeed. To roll 5x5 get special dice numbered 0-5 or just use normal 6 sided dice and count the six as 0. Roll 2 dice and multiply them to get a result from 0 to 25.
0 always succeeds. So, if you are trying to do something that you don't have a trait for, roll the 5x5 roll and try to roll a 0.
If you have a trait on your character sheet and roll the value of that trait exactly, then that's a critical success. Something great just happened.
Doubles are bad. Doubles never succeed and usually mean that not only has there been a failure, but it is the worst kind of failure. We call this a fumble. The only time Doubles aren't bad is when you are rolling to Avoid Trouble related to your Trouble Trait.
When you roll Doubles you get a Karma Point. Use a Karma Point to re-roll a failed roll. You can even re-roll Doubles but you don't get the Karma for that Doubles roll if you re-roll it, because it never happened.
You also get a Karma Point any time you are called upon to roll against your Trouble Trait to try to Avoid Trouble. The GM will try to use your trouble trait to get you into trouble. Yes, when you roll Doubles while trying to avoid trouble you are awarded 2 Karma Points.
Most rolls happen on the player side. Roll to succeed at a task or to overcome challenges in the environment. In combat, roll to attack, or roll to avoid an attack. Combat tends to be handled in broad strokes. The GM generally won't need to roll anything.
If something bad happens to you (like in combat, for example) the GM will assign a "strike" to your character.
A strike is a descriptive status marker that lets you know that your character has been through something that has diminished them in some way. "You have a scratch on your cheek." or "You gasp for air and feel pain in your chest." or "You drop your head in shame and walk away trying not to cry."
Strikes can be removed with rest or the application of healing skills or magics. But, be careful because 3 strikes and you are OUT. In this case it is up to the GM what will be required for your character to recover.
Being OUT could mean that your character is too tired to continue or perhaps even demoralized, having lost the drive needed to continue. In some rare instances it could even mean death for your character.
Weapons and Armor are optional, but if it is decided that they are important to the campaign then they are defined in broad strokes. There are three categories of Weapons and Armor: Light, Medium and Heavy.
Light weapons or armor provides one re-roll per session (like using a Karma Point) specifically for an attack or defense where the weapon or armor would be a factor.
Medium weapons or armor provides two re-rolls per session (like using a Karma Point) specifically for an attack or defense where the weapon or armor would be a factor.
Heavy weapons or armor provides three re-rolls per session (like using a Karma Point) specifically for an attack or defense where the weapon or armor would be a factor.
The re-rolls per session for weapons and armor do not carry over from session to session. Any re-roll not used is lost. Karma Points do carry over and any Karma Points not used are saved for future sessions.
At the end of each session players are awarded XP (experience) to use to improve their traits. Usually 1 XP is the standard award, but sometimes the GM might award 2 XP or in super rare occasions 3.
To get a new Trait with a score of 2 costs 2 XP.
To improve a Trait with a score of 2 to a score of 3 costs 2 XP.
To improve a Trait with a score of 3 to a score of 4 costs 3 XP.
To improve a Trait with a score of 4 to a score of 5 costs 3 XP.
To improve a Trait with a score of 5 to a score of 6 costs 4 XP.
To improve a Trait with a score of 6 to a score of 8 costs 5 XP
To improve a Trait with a score of 8 to a score of 10 costs 6 XP
To improve a Trait with a score of 10 to a score of 12 costs 8 XP
To improve a Trait with a score of 12 to a score of 15 costs 10 XP
To improve a Trait with a score of 15 to a score of 20 costs 15 XP
That's our Five by Five in quick summary. The simplified combat means fewer die rolls in general and this lead to us applying Karma to re-rolls instead of as bonuses to be applied to existing rolls. It's also proven much easier to explain and to apply.
Grades of Weapons and Armor are very subjective and will vary depending upon the campaign. In a superhero campaign, I see Weapon and Armor as more a special effect of powers and not really used.
*** Edit *** -- I put a PDF version of this article in my dropbox HERE with an updated character sheet to match.