Illusion magic is actually broken and Mayhem spells prove it

I just realized on my current playthrough that Mayhem and Frenzy spells basically trivialize every encounter in the game once you hit Adept or Master level. You cast it, walk away, and enemies kill each other while you loot. There's no counterplay. No resistance check that matters. Nothing.

Compare that to Destruction where you need perks, gear, leveling, and actual positioning to make it work. Or Conjuration where you're actively managing summons. Illusion just... breaks the game's difficulty in a way that feels almost accidental.

The weird part is I see people say Illusion is useless all the time, but that's only true if you're trying to use the early stuff like Muffle or Calm spells. The moment you unlock the AoE crowd control spells, the entire game stops being a challenge. You could probably solo Legendary difficulty just by spamming Mayhem and watching NPCs murder each other.

Has anyone else noticed this? Or am I just late to the party on how busted Illusion actually is once it's leveled up?

You're not wrong, but I'd push back a bit on the "accidental" part. Illusion's always been designed as the cheese school - it's the trade-off for having basically no direct damage output. You get crowd control that actually works, and in exchange you're not throwing fireballs that melt faces.

The thing is, yeah, Mayhem and Frenzy trivialize most encounters, but they have real limitations the OP isn't mentioning. They have a duration, they have a casting time, they don't work on everything (undead, constructs, automatons just ignore them), and if you're fighting something with high magic resist or a boss that's immune, you're suddenly very squishy with no damage spells leveled. I've had runs where I hit a Mayhem spell and realized mid-cast I'm about to get deleted because the target didn't take it and I've got nothing else ready.

On Legendary with perks and gear built around it? Sure, it trivializes stuff. But so does a properly built Destruction mage with Augmented perks and stacked elemental damage, or a stealth archer with a bow. That's kind of the point of character building - you find something that breaks the game in your favor.

If it bothers you, honestly just don't use them. Or use something like Requiem or Wildlander where the balance is completely different and Illusion gets retuned. But I wouldn't call it broken so much as just... really good at what it does, which is make enemies kill each other instead of you.