How far have you explored in the game....I'm not sure what his Best weapon is
Could there be another one you haven't found yet?
Do you have and have you used the level up potion...I can't remember if it's the attack up or the weapon up that helps
Oh just had an idea
find a save point and try the potion the dude at the assassian's guild gave you...that might make a big differance...or not

....Don't forget to save JUST before you try it!!!!
just curious...I haven't triggered anything that asked me to do this yet...Why do you need to get his attack up to 2500?
Have you used forum search on this yet?
Okay out of ideas for now!
"May Fortune Sing to You Her Sweet Song and May You Live and Love Way Past Long!" Sonny Landreth