How does Forgery even make sense??

Like, there's no quest attached to it. The corruption hasn't even spread to gavel yet, and the forgery wasn't a result of the corruption. So how are the dungeons corrupted?? I don't get it. Also I just noticed this, but it's located right between the dark and light forest. Did the corruption somehow manifest there? If so, why isn't it spreading to cinfras/whatever?

 

its a possible future where the corruption has taken wveything

 

Basically there were runes and they exploded and now there’s a forgery

 

The power of fusing runes resulted in the island being formed, with entrances to "parallel" or future universes where the corruption is victorious.

 

There is a whole secret discovery about this

 

I haven't done the forgery secret discovery yet, but I think the dungeons in the forgery might be, as the name suggests, forgeries, so not actually corrupted