Parry, Dodge, Roll with Blow

[danzig138]

A few years ago, I used to run a Rifts game. Eventually, I got tired of trying to fix the things that needed fixing. However, there was an aspect of the system that my players liked, and still periodically bother me to include in my d20 games, and that is the systems of dodges, parries, and rolling with blows used in Palladium's games.
So I finally decided I would see if I could find a way to incorporate these into my games. Near as I can tell, I can pretty much directly port the rules into the d20 system with little effort, but as I was looking, I started wondering. With the much more active defense system this brings, I can't help but think that the base chance to hit a target should maybe be changed. I have no idea what to make it though. Straight up 10? Lower? Higher?
Keep in mind that IMG, armor does not add to AC/Defense. So armor bonuses are not a factor. Thanks in advance.

 

[Tonguez]

I don't know what the RIFTS rules are so wont comment

but imc I sometimes use active defense (parry, dodge etc) by allowing PCs to roll for AC thus D20+Defense skill+Dex and use this instead of AC. Defense skill is a new skill I've added that uses BAb rather than normal skill points (ie a PC can split their BAb)

 

[Bihor]

Good idea . but does this make a lot of rolls

 

[Primitive Screwhead]

Check out Kenneth Hood's Grim-n-Gritty and Martial Arts systems.

The GnG is available on EnWorld, osrry not good at getting links in my post.

The Martial Arts system has blocks, parries, and an ability called roll with the blow, which can reduce the amount of damage taken on a hit.

Good system, but very radically changes the game.

 

[danzig138]

Good idea . but does this make a lot of rolls

Yeah, it can make for a lot of extra rolls, but, optimally, the target makes his rolls at the same time as the attacker makes his rolls. Of course, I was never able to train my group for this. Just like I can't get them to roll damage at the same time they roll their attack roll.

 

[Aeric]

Here's how I would do it:

Base Defense: 10 + any situational mods (cover, deflection spells, etc.)

Dodge: d20 + Dex bonus + Dodge skill or class-based defense bonus (a la UA or SWd20)

Parry: like a normal attack roll, only the "AC" is your opponent's roll to hit (an opposed roll)

Roll With Punch/Impact: maybe a Reflex save with some heavy modifiers? IIRC, roll w/punch is usually easier to do than dodge or parry, but at the cost of taking half damage.