d20 is designed, in a meta-game sense, for the PCs to end up as deific beings with manga-comic super abilities. That is great fun except when you don’t want those beings to be possible. One might say that d20 is the wrong system however I say it’s an okay system that is like learning blues on guitar. It lets you jam with anyone.
Gritty is just code-word for “dangerous”, or the possibility that you can die quickly in combat: kind of like real life. So here’s some options:
1) Hit points max out as Str + Con + Base Fort Save
2) Critical strikes automatically inflict maximum damage
3) Death starts at –1 HP.
4) Heal spells aren’t instantaneous – they’re overnight; thereby forcing them to be combined with rest.
5) Any critical strike (regardless of if you use 2 above) requires a Fort save of DC 10 + damage inflicted, or the target is stunned for 1 round.
And one can go on.
Shields are great – particularly when your opponent doesn’t have one. There’s a few ways to better model this in d20-based systems (like DnD, OGL, SRD, etc).
1. Instead of the shield’s AC bonus you can use the shield to “soak” damage. Convert the shield’s AC bonus to Damage Reduction. You become easier to hit but harder to damage. This is the willingness to take a hit on the shield.
2. Forfeit the AC bonus of the shield. Instead make a roll to “soak” the damage with the shield if you are struck. In v3.x roll vs. a DC of 10 + Opponent’s BAB + weapon specialization (and the like). The shield-wielder adds their BAB + shield specializations (and the like). Each point of success reduces the damage by an extra point.
Eg. DC is 19. Roll a total of 21. Reduce damage by 3 (19, 20, 21).
2a. Shields can be given a maximum damage they soak before they “splinter”.
Eg. a buckler might be able to soak 15 damage before it splinters (is made useless).
3. When one has a shield and the opponent does not double the AC mod.
The point here is that with a little bit of thought shield function can be better reflected in any system.
(Image from: http://etc.usf.edu/clipart/58600/58671/58671_kite_shield.htm )
I’ve been resisting for a long time but it’s such a massive market to deny. After playing a bit of d20 (DnD) with the Eclipse: Codex Persona, I’ve found it fun for the first time in years. There are still some core ideas that I find rather silly and the spells tend to have far too great a range, but I’ve got it in my head that making Khara Thel for d20 would open it up to a much larger audience. It’s a lot of work, though, and I’ve got no idea how long it’ll take me to do.