Not finding DRK squishy at all.

[BadRNG]

Equal level, not yet.
But we checked on overworld monsters, like peistes near Bluefog.

But it seems to us that an higher level, with more defense and elementral resist should always take less damage. I even removed my shield to prevent some invisible bonus that might apply.
But I'll do more test as soon as I can

It makes the most sense for us if it did work like that, higher number = better effect, but it's not how the game really handles it. Stats scale differently depending on your level, it takes more of it to have the same effect. If it didn't work this way then eventually, after enough expansions/gear upgrades, we'd all be running around with 100% defense, crit, parry, etc.

It wouldn't hurt to test some more to be certain but I think that is what is happening here.

[Reynhart]

If it didn't work this way then eventually, after enough expansions/gear upgrades, we'd all be running around with 100% defense, crit, parry, etc.

As long as Defense, Crit, Parry, etc...are tied to the difference between stats, you could always stay in reasonable numbers. Yes, you'd have godlike stats if the mob if too low for you, but it's hardly relevent.
(In fact, in 1.xx, that was the case. As a PLD50, with a Rage Of Halone, I'd do around 500 damage on a lvl50. And around 4000 on a lvl40.)

I don't understand how, towards the same monster, having more defense makes you take more damage.