[A16] Fist attack There is no attack button.

[East]

http://i.imgur.com/rExvkXG.jpg check this image

I think that it is not the intention of the development team that the scythe blade is put on the fist but it does not attack the fist. Even if it is not, I think that attack button is necessary for fist attack.

[zeidrich]

I think this is WAD. 

The attack button because of an equipped weapon.  You have modified limbs, not an equipped weapon. 

You can still attack by right clicking a target and choosing melee attack target.

While an attack button might be an option, it doesn't exist for unarmed attacks whether you have scyther blades, power claws, bionic arms, or regular fists.  Similarly, even with combat-augmented arms, you can still use a weapon, so you need access to the weapon-specific options.

[ison]

As zeidrich said you can still right click and choose the melee attack option. I think there's no need for an extra command per each modified limb, and it could cause confusion when you have a weapon equipped. Thanks for reporting anyway.