Greetings, I am here to suggest, and subsequently get a blitzneedle's worth of holes poked into my idea.
What idea? Greatswords or I guess they'd act like a form of parrying sword.....It was in the topic's title.
Alright, just hear me out. This isn't an idea for a normal type of weapon, this is an idea for a shield replacement.
---How would it work?---
It would be equipped in place of a shield and serve as a way to give people a form of risk/reward gameplay.
When a player would press the defend button, a knight would pull the sword off their back and do a very short duration block. If the block would intercept an attack it would be deflected and a counter attack would be unleashed, with some I-frames. This 'parry' would have a short cool-down in between, getting fully reset if you successfully parry an attack.(In the way as, if you parry something, you can do it again.)
---What about shield bash? Or shield bump?---
The shield bash button would be replaced with a big ol' attack with said greatsword. And shield bump? You'd still do that, just at the end of the 'parry' as to not fling away the parry bait that you worked so hard to get.
---How would this work against ranged attacks?---
Similarly but without the counter attack.
---How would it be handled on our characters? Just holding something in our offhand?---
Nah, I'd be on your back, ready to be pulled off by your now naked off-hand.
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That's the idea in a nutshell. Of course i can't stop y'all from giving your thoughts. And would like to know how many flaws my idea has.
Nah, too heavy. We already have enough issues with swinging a thwack hammer.