The Void Area

[T.Lightning]

What's up with the area behind Dis? (NPC where you can buy skills) , i found a platform with hellhounds that when you press the action button War/Strife pets them.

if you go in the other direction and head north from the middle you eventually reach a place where 1 side is red other side is green, around the area between the rocks are golden objects(??),

if you go a little further north there is a huge Ballista you can shoot but does nothing else? and the other path leading East is a platform that ends, if you jump off and use your glide you can see a boatman coin on a pillar , haven't found a way to reach it yet

Anyone with some more information about this mysterious area is well appreciated

[RCMidas]

As you complete more sidequests in the missions, you unlock progression through this place, the Boatman's Maze. As you then complete more challenges here, you get to collect more Boatman Coins from here.

[Aedra]

it's a quest and achievment Garden of Forking Paths

Collect every Boatman Coin in the Boatman's Labyrinth.

After you complete some Missions and Side Missions, some of the area mechanic will be unlocked for you to do another puzzle for boatman coin.

For example,
petting dogs in correct order
balistta: just keep using it
collect all gold ingots

etc.