For: Unique weapon; built as the largest weapon meant for a medium character, despite its size and needing a feat. It's meant to supersede a greatsword in base damage at the cost of a feat.
Against: You can just substitute a large greatsword if the damage output is the same and it would still require a single feat.
Overall, depending on DM interpretation, the fullblade can be the most devastating base two-handed weapon in all D20, or the biggest let down if made an over-glorified large greatsword.
My personal argument for use of a base size fullblade is really just how much harm could it bring? A 1st lvl fighter would find this the best 1st lvl weapon ever. it's balanced because, unless you can bargain with the DM, you can;t dual-wield it so eventually a dual-wield greatsword barbarian will just come along to boast how he can hold two slightly smaller weapons in each hand.
This isn't a rules question.
I don't think you fully understand where to post yet.
Please check to find the appropriate forum prior to posting.
Oh... is there a general discussion forum?
How do I delete or move posts? I wanna move this into general discussion.
You Flag it and choose the move to another thread option.
Anyway, I think the Fullblade is silly and will lead to shenanigans when players start increasing size.
It starts out as +2 average damage over a Greatsword (Fullblades are 2d8, right?), but when you get Enlarge Person, Lead Blades, the Impact weapon quality, it gets bigger.
I don't have a problem with spending a feat to get +2 damage--those feats exist. I am just wary of size increasing and, well, I think it's completely stupid and unnecessary, aesthetically.