I am about 15 hours in on GMGOW and so far nearly every fight has killed me at least once. Usually about five times. In some cases twenty. And the vast majority of fights have no more than four enemies in play at once.
On the hardest difficulty setting, this game does not fuck around at all, from the get-go. There are no popcorn enemies or punching bags. There’s an interesting mechanic where damaging most enemies causes them, in an interruptible transformation, to become enraged and thus more aggressive and stun-resistant. The need to prevent this demands you play aggressively and surgically. Since everything also packs a lot of health (the complaint many use to dismiss the mode, even though it changes a lot more than just that), and since most fights consist of mixed groups that all pose different threat vectors aside from their attack timings, you must constantly vary your attack approach out of necessity rather than button-mashing style points. There are no systems which serve to trivialize the rest of the game, such as Bayonetta’s Witch Time, and healing is mostly OSP and scarce (no regenerating, no inventory items aside from one equipped talisman of whatever ability on a cooldown).
Also, since you only have your axe and your fists rather than a wide variety of weapons, the game has more detailed poise mechanics per-enemy than most beat-em-ups, and thus encourages you to adapt different light/heavy attack strings to maintain pressure.
The game is strongly holistic and demands you use every tool you have available, then keeps giving you more tools, then keeps throwing more types of enemies at you. It’s great.