Huge. gargantuan. and colossal weapons?

[largo1337]

Hey there. I have a person in my campaign who is running a big weapons character. He is a goliath which allows him to wild weapons as if he was large even though is classed as medium. He is also running a homebrew class (that i have allowed due to its utter lack of additional abilities) that allows him tho "wield a weapon of one size category larger than it already can" so he can wield a huge weapon (greatsword is his choice) he also has sizing enchantment on it so he can make it bigger at the loss of accuracy. And smaller so he can actually transport it in standard buildings

My question is: how should his attacks work? A huge greatsword is probably at least 12-15 feet long but as a full blade can slash should everything within 2-3 squares get hit depending on his swing style (conical attack for horizontal or line attack for vertical) i am currently only allowing single targeting as is standard attacking. But it feels kind of... Incorrect. I could easily nerf the cone/line ability with obstacles such as structures or trees therefore forcing him to either stab with it or attack with the pommel. I gave him 10foot reach with it for now but i would like some insight into how to deal with this as a DM

[atemu1234]

However you want it to work, really. I'd say that it doesn't increase his reach, because he can only effectively use it on something adjacent to him, like something his size. Damage still increases due to the size of the wound, but the ability to hit things doesn't vary because his reach doesn't vary.

[Anxe]

I had an NPC that did that once. I ruled that it did not increase his reach. I think there's a monster feat for hitting multiple squares in the MM or in Savage Species. If there isn't it'd be easy for you to homebrew one and adjust as needed.