The Crossroads of Dragon Age: The Veilguard includes several disconnected areas. The fourth area is the Heights of Athim, and it features a large tree that's almost completely overcome by Blight.
Like many Blight growths in Dragon Age: The Veilguard, you can remove some of the Blight to clear a path and get some treasure.
Your companions will remark on the tree, just to make sure you know there's something you can do about it. However, this Blight growth has a unique requirement that some players may struggle with.
Whether you figure out the Blighted tree's requirement or not, the first thing you need to do is figure out how to reach it.
There are plenty of Blight boils in the Heights of Athim you can pop, but none of them will have an effect on the Blighted tree. Instead, the tree uses a completely different mechanic to become vulnerable, and you can find out what it is by walking right up next to it.
When you do so, a bar will appear, which says "X/50 Darkspawn Killed." Once you hit the number 50, the central mass will start glowing, and you'll be able to destroy it.
There's one big problem with this counter: Even if you explore every corner of the area, you won't find 50 darkspawn.
So, how can you reach this number?
Once you reach the magic number, blast the glowing patch of Blight to open a path into the tree's hollow interior. You can then open a major treasure chest to get a unique item, which might be the Maw of the Black City, a unique ring that lets you deal critical damage with all abilities but sacrifices 20% of your health each time.