D&D 3E/3.5 How backwards compatible to 3.5 is Pathfinder?

[am181d]

As I've mentioned elsewhere, I'm starting up a new 3.5 campaign soon, and while there's plenty of 3.5 material out there (both WotC and 3rd party), I also like the idea of having Pathfinder available as a source of new content.

The problem is, I'm just not clear on how compatible Pathfinder is with 3.5. Can I take a Pathfinder feat or spell or monster out of context and drop it into a 3.5 game? Where will I run into trouble? What are the subtle differences I should watch out for?

Is there a 3.5 to Pathfinder conversion guide out there somewhere? (Or a Pathfinder to 3.5 guide, although I suspect that's less likely to exist.)

Thanks!

 

[Stormonu]

Pathfinder to 3.5 will probably actually work better than the reverse. Though I have to admit I'm still new to Pathfinder (the characters have only reached 3rd level), I'm using the 3.5 Rise of the Runelord modules and I haven't run into any compatibility problems so far, and the characters are almost finished with the 1st adventure - at this point, just a few more rooms and they'll be done with Burnt Offerings.

 

[tylermalan]

I played a lot of 3.5 back in the day, and I've been playing Pathfinder (PF) for about a year I would guess.

I believe there may be a 3.5 to Pathfinder conversion released by Paizo, but I don't know for sure.

You can probably drop select Pathfinder stuff into a 3.5 campaign, though why you would want to I don't know. Just play Pathfinder. It's better.

There might be some stuff that you can't just drop in, though. For instance, in my experience, the PF classes are more powerful than their 3.5 counterparts. Because of this, the PF monsters are a bit stronger in some cases while the CR hasn't really changed. So if you use, say, a CR 3 monster against a party of level 2 characters, that monster might have the power of a CR 4 monster in 3.5.

At the same time, if you allow the usage of Pathfinder stuff in the 3.5 game, there is NO reason why a player would prefer to take a 3.5 class over the PF equivalent.

 

[IronWolf]

This Handbook can be useful to highlight some of the differences between 3.5 and Pathfinder:

The 3.5/Pathfinder Handbook - Giant in the Playground Forums

If it were me I would likely avoid mixing the two too much, even though they are supposed to be compatible. With the amount of Pathfinder option books available and the trove of 3.5 option books available I suspect an overload of options to merge the two. That is just my opinion though. You have to do what you think will be most fun for your game.

 

[billd91]

I'd say PF is about 90% compatible with 3.5, particularly using 3.5 materials in PF. I've used modules with hardly a tweak save for adding CMB and CMD to the monsters and noting that Spot/Listen are now Perception.

Going the other way, using PF characters in 3.5, you'll probably find the PF characters a bit tougher in general because some have more hit points, some have a few expanded powers. This isn't necessarily a bad thing since most of the improvements are in classes that needed them.

 

[Crothian]

Converting for the DM either way seems to be pretty easy and work well. For the player though I wouldn't do it as it can cause balance issues.

 

[am181d]

I played a lot of 3.5 back in the day, and I've been playing Pathfinder (PF) for about a year I would guess.

I believe there may be a 3.5 to Pathfinder conversion released by Paizo, but I don't know for sure.

You can probably drop select Pathfinder stuff into a 3.5 campaign, though why you would want to I don't know. Just play Pathfinder. It's better.

There might be some stuff that you can't just drop in, though. For instance, in my experience, the PF classes are more powerful than their 3.5 counterparts. Because of this, the PF monsters are a bit stronger in some cases while the CR hasn't really changed. So if you use, say, a CR 3 monster against a party of level 2 characters, that monster might have the power of a CR 4 monster in 3.5.

At the same time, if you allow the usage of Pathfinder stuff in the 3.5 game, there is NO reason why a player would prefer to take a 3.5 class over the PF equivalent.

My group has a pretty visceral dislike of 4e, and one of the appeals of 3.5 is that they've already got all the books and are really comfortable with the system. We're playing online (using Skype and Fantasy Grounds) so I don't want to over complicate things by making people learn a slightly different system.

At the same time, as the DM, if I've got a source where I can pull in new stuff that they generally won't have seen before, that's a win-win. (Or possibly a win-TPK, I guess...)

 

[Glade Riven]

Depends on the 3.5 stuff, really. Later 3.5 stuff that was a bit over-powered works fine with Pathfinder and vise-versa. Weaker 3.5 stuff may need to be assest, and some of the combinations can get pretty crazy (there is a wizard/9 fold path/warcaster in a party of a friend's group, and it gets a little over-powered). Pathfinder CRs are a little bit more useful than 3.5 CRs, so with monsters I'd probably assume a +.5 or +1 CR as someone mentioned above.

 

[Tovec]

I'm surprised no one linked the pathfinder conversion guide. It's free from Paizo.com and explains the basic changes between 3.5 and PF (at least as far as the Core is concerned).

I would start there when trying to understand design changes or feats that have changed and how they work now.

In general, feats especially, most material in PF should work in a 3.5 game and a lot (though probably not "most") 3.5 stuff works in PF. Even some 3.0 probably works well too.

The modules and adventure paths are specifically designed to fit into 3.5 as the Pathfinder setting started out 3.5 entirely before the core rules were rebuilt. So take a look at pathfinder stuff and try it out is the best advice I can give.

I do echo the sentiment here though, Pathfinder is a much prettier system and I can understand not wanting to change. When I first got my hands on the core rulebook and our group started playing it was with the idea that we keep our 3.5 stuff and use PF as well but that idea quickly dissolved through gameplay as we had so much more fun and better experiences with PF.

 

[tylermalan]

My group has a pretty visceral dislike of 4e, and one of the appeals of 3.5 is that they've already got all the books and are really comfortable with the system. We're playing online (using Skype and Fantasy Grounds) so I don't want to over complicate things by making people learn a slightly different system.

At the same time, as the DM, if I've got a source where I can pull in new stuff that they generally won't have seen before, that's a win-win. (Or possibly a win-TPK, I guess...)

Yeah, I get that. Really, though, since the changes to the rules themselves are minimal, it would be a very small effort on a player's part to learn them. Comfort with 3.5 is comfort with Pathfinder, 99% of the time. I guess the only major changes are those with the classes.

Regardless, I would say you'll be fine if you are careful that stuff you include from Pathfinder isn't too powerful.