Synthesist Summoner multiclass?

[Dhurkan Blackblade]

I was wondering if anyone could give me some advice. I am creating a character for a homebrew sci-fi/bio punk campaign. 5th level 9000gp but only mundane items, no magic at start. I have a concept of a Synthesist but I am concerned about damaging enemies once DR comes into play. So I was thinking about dipping into Soulknife to pick up a psi-blade to bypass some DR...thoughts and suggestions are appreciated!

[Taku Ooka Nin]

Get an amulet of Mighty Fists.
Now, upgrade said amulet of Mighty Fists to +5.
Congratulations, now only DR/- and DR/epic stop your attacks.
Maybe DR/Adamantine, but I don't remember.

For the summoner there is literally no reason to multi-class.

[ArmouredMonk13]

Multiclassing is generally a bad idea for the summoner, as it nerfs your eidolon. Try getting some nice damage behind your strikes, and getting a +3 AoMF so you can overcome Cold Iron/Silver DR, Magic DR, and then for other DR you just have to take it. It will max out at 40 for all of your attacks, if the creature has DR 10 and you have 4 natural attacks.

[Dhurkan Blackblade]

Thanks for the info, and hopefully we will get magic items. As of right now, we cant purchase any at the start.

[Kaleb the Opportunist]

I shouldn't even share this but 2 levels of paladin on a synthesist Summoner has been proven to be ridiculous. Max Int and Chr on your Summoner and dump Str and Dex. The eidolon takes care of those. Smite overcomes all DR and all your saves will be excellent.

[LoneKnave]

Depends on if you want to use Synthesist as a stat-dump machine dip to get good mental stats, or do you actually want to stick with it.

Synthesist+monk can get stupid AC, Synthesist+Paladin gets stupid saves. In fact, just about any melee-type can benefit greatly from a synthesist dip because of the first level pounce they can get.

An interesting build is small sized serpent base eidolon with a lot of arms, pistolero, about 20 guns, and the leaping shot deed.