Guild Wars 2

Before the last Living Story update, on the northern part of the map it appeared to be a big lake. What happened with it? Seems that the low detail map was not respected.

Well if the low detail map is based on what the ingame characters think is there. (which is than replaced with what is actually there once they see it) This could be explained by the fact the last time the ingame characters went to the Maguuma it was still the maguuma jungle, with lakes etc. However due to an unknown event (possibly Mordremoth) the Maguuma jungle has dried out becoming the Maguuma Wastes.

This would mean the lake which can be seen on the low detail map has just dried out over the years.

Source: http://wiki.guildwars2.com/wiki/Maguuma_Wastes

Yeah…but when the episode released, there was a bug where the characters could swim on sand…

It could be underground.

Most likely dried out. Ring of Fire probably shrunk too due to Orr.

Edit: Wouldn’t be surprised if the crystal desert got screwed as well.