Ichibanmon wrote:1)Is it possible to use knowledge to add to the damage multiplier.
No. You can potentially justify the Knowledge as part of your Attack Roll, which will already boost Damage.
2) should knowledge be used in the attack roll as well as the damage multiplier simultaneously.
As a general rule, nothing should ever add to multiple things simultaneously. You can't add something to your Attack Roll and your Defense Roll, or your Attack Roll and your Damage Multiplier.
I'm sure someone can root up an exception for some duplication, but generally adding something to your Attack Roll and your DX is effectively getting double the bonus from one Ability—which isn't really fair.
[3) would it be a good idea to offer one over the other
Whether something that adds to your Attack Roll or to your DX is the better option depends on the situation and what you consider better.
Generally adding dice can get you better potential gains, but ones that only activate randomly (that is, with good rolls). DX bonuses only add more modest gains, but consistently do so with every single roll. DX is also more useful against opponents with
Armored, since it negates that penalty on a 1:1 basis.
On average though, they're pretty equivalent.