Quest: Breaking the Limits

Quest level: soul tree level 60
Location: Nightfall (mostly north of the Citadel)

Once you get to level 60 in your soul tree you will be able to pick up a quest that will allow you to open up the other side and build that up as well. This quest does get to a part that seems like it will switch you permanently to the other, but it doesn't, so ignore that. You will actually be able to switch as often as you like with a 300sec cool down. This means that you can pick which ever tree will serve your particular purposes at any given time. Nice.

You will not need to do another set of soul gates, but you will need to gather more soul power to upgrade and utilize the power in the new tree. You will also need to set more runes to power up those talents. There goes all your gold again. *sigh*

To get the quest, first break your level 60 gate. Next take the quest from your leveling guide (press H and take the Breaking the Limit quest). You can also pick this quest up from Ferrie, the npc outside the library that gives you free heals.  You should get this quest automatically. The quest itself was pretty straight-forward, similar to, but far easier than the original dyos/nyos quest. It is annoying in that it has you going back and forth between two npcs that appear on the map to be very close to each other, but the auto-routing will have you travel all over the countryside - use a flying mount.

After you get Velastus (again), you will need to go back to the guys that you talked to when you originally chose dyos or nyos. There will be a ! above the other guy's head - so it is easy to know who you need to talk to in order to finish the quest. He will say that once you choose, there is no going back - ignore that. In red you will see a caveat that lets you know that for this particular quest that does not apply. When the quest asks you to talk to the soul - you need to right click Velastus in your bag to talk to the soul in the sword.

Once you open the second tree, you will get the skill for activating that tree. You will use this skill and the one that came with your original choice to toggle back and forth between the two trees (with the 5 minute cd, of course).

By the way, this quest gives you 120 soul leaves!! So even if you really don't want to switch, it's worth it for the leaves alone :)