Synthesist, natural attack, claws, two handed weapon

[Yogmoth]

Hi, I'm building a Half-Elf lvl 4 summoner - synthesist.

Sorry if this has already being answered but after some digging i haven't come to an answer.

Because i'm a bid afraid of the synthesist percieved power, I don't want to rely on a permanent eidolon but rather want to use it has a panic button when things get really messy.

The basic idea is that the character will be wearing a two handed weapon (No Dachi, just for the style).

I want a bipedal eidolon, so he starts with two hands, legs, and claws. I don't want other limbs.

You can make attacks with natural weapons in combination with attacks made with a melee weapon and unarmed strikes, so long as a different limb is used for each attack. For example, you cannot make a claw attack and also use that hand to make attacks with a longsword.

When you make additional attacks in this way, all of your natural attacks are treated as secondary natural attacks, using your base attack bonus minus 5 and adding only 1/2 of your Strength modifier on damage rolls. Feats such as Two-Weapon Fighting and Multiattack can reduce these penalties.

From what I understand from above:

-can the Eidolon/me make a NoDachi attack then the two claws attacks as secondary attacks (if the hands have claws) ?

-if it is not possible, can i do the same with slam (arms) instead or claws ?

[Taenia]

The default biped eidolon has claws on his hands. If those hands are wielding a No Dachi then they cannot be used to perform claw attacks.

Slam is a bit of a problem. Their are cases where slams are apparently using the arms limb and other cases where they use something else, for example dolphins or elementals.

Because eidolon slam requires the attack based on number of limbs (arms) you have I will assume you have to have those limbs free to make slam attacks.

If you want to wield a weapon and add natural attacks as secondary you will have to go for a bite, gore or tail + sting. You can also, since they are already secondary use attacks like tentacles or tail slap.

Given you limit on other limbs, the bite and gore seem your best bet. If you want to give him a more humanoid flavor you can have the gore be from a "horned helmet" and the bite from a modified "visor" or something similar.