Venge's aghs in Nest of Thorns is broken
I've played enough Nest of Thorns that I can say with confidence - starting from patch 1.1, Venge stun's Aghanim is broken and doesn't work, the damage simply isn't added.
A couple of screenshots show that the damage before and after Aghanim was roughly the same. 100-130.
The same can be seen in the final damage statistics, I even managed to get a record for damage from a stun without Aghanim.
