Casts:
Anguish of the Body-- Limits hps to 50% of total. 25 Corruption counters.
Anguish of the Soul-- Reduces skill damage and reduces attack speed. 25 Corruption counters.
Not sure if single or group. My bots were out of my group with the other bot.
Rolf hits for 29k non disc.
From my parse of getting him to about 50%, he has in the range of 75-80 million hps.
Spawns adds, I don't know what the conditions are, I couldn't find any correlation. They're called "a shadow of despair", they hit for 16039 max, and have low hps (about 500k)
The mob nearby his spawn will not aggro if you keep him in the corner. Nothing roams to you.