They love souls and hate archons. The default heavy, the tormentor, has countercharge. Their heavies are steady. Each master has a niche playstyle its best at. They feel stronger vs living models because they benefit from souls. Thus, archons really tend to screw them. They ars best early to mid-game. Weather the assault and play the long game, they fall apart late game.
Love, sex, pain, confusion, suffering You're there crying, I feel not a thing Drilling my way deeper in your head Sinking, draining, drowning, bleeding, dead
We have probably the best answers to infernals out of any faction.
Krueger 2 bones shuts down their soul generation and has respectable threat. There's also the problem that they'll just loose on scenario. Good infernals players will give you a 50/50 game into krueger 2 which is pretty respectable considering he's the go to for the baldur 1 pair.
Kromac 1 shuts down their entire essence generation and Agathon assassinations. However kromac sort of wants the spot baldur 1 or Iona takes up in the generalist pairing. Due to the fact that kromac is generally not camping much and is always looking not to get shot to death as you might imagine. This is something Krueger 2 can play well with.