Planning on running 3.5 again after 10+ years of Pathfinder, advice?

[genderlich]

So I had an Eberron campaign idea that I really want to run for my group, who have played Pathfinder for 10 years (originally 1st edition, have switched to 2nd edition). I enjoy 5th edition pretty well but have no interest in running it, and I didn't want to try converting all the Eberron stuff to 2nd edition Pathfinder, and I'm honestly really sick of 1st edition Pathfinder, leaving me with only one option--run D&D 3.5.

It was the edition I grew up with, and I'm excited for the nostalgia factor, but having not played it since 2008, I'm finding myself a bit lost to keep track of what the changes were and how the system runs differently than PF1. What are the major things to keep in mind that I'm going to have to unlearn or relearn?

I was planning on saying no tier 1 classes just because I know that was an even bigger issue in 3.5 than in PF1, while allowing core, psionics, and the Complete series. I also know 3.5 got really heavy with alternate rules and subsystems--what are some of those to consider and which ones should be skipped over?

Any general advice on running 3.5 would be appreciated as well! I'm very used to the Pathfinder classes, feats, monsters, and magic items at this point, so I'm unfamiliar with the good, the bad, and the ugly elements of 3.5.

[Kurald Galain]

I've found the main difference is that, if you're used to PF, low-level 3E is pretty boring. You don't get to choose your traits, bloodline, rage powers, and whatnot; you get less feats, effective skills, and spells known; and you have to start planning ahead for what prestige classes you want at mid-level. Character concepts that work at level 1 or 2 in PF often require level 8 to 10 before they work in 3E.

E.g. if you ask for a Gish in PF, you play an out-of-the-box magus or warpriest from level 1; whereas the same idea in 3E requires two base classes, several prestige classes, and about nine levels before it does what it's supposed to.

So yeah, I suggest starting somewhere between level 5 and 10, really. And in addition to avoiding tier-1 classes, avoid tier-5 and tier-6 classes in 3E. HTH.

[Pinkie Pyro]

Why not just do both?

3.P is a valid way to play.

is there a reason you want specifically 3.5?

[Crake]

Why not just do both?

3.P is a valid way to play.

is there a reason you want specifically 3.5?

Definitely agree with this sentiment. 3.5 as a base system, but just backport whatever pathfinder material you want. Do you want traits? Include traits. Do you want pathfinder classes? Backport them over with usually little-to-no effort.

[Psyren]

Any general advice on running 3.5 would be appreciated as well! I'm very used to the Pathfinder classes, feats, monsters, and magic items at this point, so I'm unfamiliar with the good, the bad, and the ugly elements of 3.5.

+1 to what everyone else said about just combining the two - but if you're dead-set on pure 3.5 for some reason, you'll have to decide what to do about some of its rules that PF1 left behind, e.g. XP costs, multiclass penalties, cross-class skills, unconsolidated skills etc.

[GoodbyeSoberDay]

Let me start with agreement - you have experience with PF, so you might as well allow some stuff to be back-ported in. Both systems are about having solid crunch support for a wide variety of concepts.

That said, there is a big misconception in this thread. 3.5 and PF are, by design, very similar. This is in part why it's so easy to back-port. Now, PF streamlined a lot of things and made things easier - just putting everything on the SRD is a huge improvement, and PF requires less dumpster diving and planning ahead on the build - but to suggest 3.5 is incapable in key ways comparatively betrays a lack of recent 3.5 experience. The two most glaring examples to me are the fact that the Duskblade exists, and that in both systems low levels are designed to be a mere stepping stone on the hero's journey. But it's not like 3.5 is incapable of producing concepts at low levels; you just have to look a bit harder.

Regarding some of the OP's questions:
- Many PF subsystems are close analogues of 3.5's subsystems, so if you're familiar with them you can either back-port them in or allow the (probably slightly less polished but already-integrated) 3.5 version. Examples: Psionics, initiators, incarnum (this one has a bit of a learning curve but is easy once you get the hang of it).
- Depending on your group, the full casters are going to pose similar problems in either system. If you didn't need to ban T1 in PF you probably don't need to in 3.5. That said, if you are banning the prep full casters, then you have created a hole in 3.5 where there wouldn't be one in PF. Much of the native support for casters went to these now-banned classes back in 3.5, so you probably want to bring the Oracle and some of the 2/3 casters back from PF in this case.
- Specific 3.5 things: Look up banlists. You probably had a ban/houserule list for PF; you'll need a slightly different one for 3.5. Examples to ban or modify: Synchronicity, Wings of Cover, Incantatrix, the "Taint" mechanics.