The only problem I have with the spiked chain is that compared to other exotic weapons, it offers too much.
- It can be used in close OR at full reach.
- It gives bonuses to both Disarm and Trip
The other reach weapons cannot be used in close without the Short Haft feat from the PHB2. For Disarms, the Spiked Chain is at +6 (2 handed plus weapons bonus). You don't even need improved disarm, just do it from 10 feet away. And the other exotic weapons in the PHB are all either double weapons, or the Net or the Bolas. Double weapons are nice, but full use is fairly feat intensive. The Chain is not at all feat intensive, and unlike the Double weapons, you can get good use out the the feats that work well with the spiked chain when using other weapons. Imp Disarm, Imp Trip, and Combat Reflexes are all good to have with any weapon.
My biggest problem though is combining this weapon with Cleave / Great Cleave. Reach + Close is just too good. No other weapon gets to work both in close and at range at the same time. Even using Short Haft, you have to basically choose reach OR close once per round. A fighter with a solid Str score who takes Power Attack, Cleave, Great Cleave, and Exotic Weapon Spiked Chain can mow down retarded numbers of Orcs / Goblins. Add in Combat Reflexes and they pretty much cannot touch him if he also has a half decent Dex. A human fighter can achieve this at Ftr 3. I still get good milage out of 1 HD opponents at those levels. Still, I just don't really know if there is a reasonable fix for that.
Would you throw an optimized 3rd level Fighter villian with the above feat combo against a CR apropiate party? I would be very hesitant to.
Compared to the other Exotic weapons in the PHB, the Spiked chain is just much better because it works so well with so many options.
I also find getting 1.5 Str bonus from a flexible weapon like the Spiked Chain to just be aesthetically displeasing.
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