Shield Bash

[Egres]

From the FAQ:

Can a character make a shield bash attack using the
shield as a primary weapon or can it be used only as an offhand
weapon?

While the rules describe a shield bash as an off-hand
weapon, that’s simply an assumption (that your primary hand is
holding a weapon). There’s nothing stopping you from
declaring your shield bash as your primary weapon. Of course,
that means that any attack you make with your other hand
becomes a secondary weapon.

 

[Legildur]

From the FAQ: <cut>

I take exception to the FAQ in this instance since it is not simply a matter to declare it a primary waepon. The half-strength bonus to damage is a result of wielding the weapon in the off-hand.

The glossary of the PHB says the following:

off hand: A character's weaker or less dexterous hand (usually the left). An attack made with the off hand incurs a -4 penalty on the attack roll. In addition, only one-half of the character's Strength bonus may be added to damage dealt with a weapon held in the off hand.

So you would need to be wielding a shield in the primary hand in order to declare it a primary attack... which would mean wielding a 'normal' weapon in your off hand, with the associated penalties...