Yup. Pretty much everything.

I mean spells learning rate are not affected bt mob lvl and communes are

Uh, 99.98% sure spells are, as well as any in-combat skills.

Tougher the mob you're fighting, the faster your skills improve. Weaker it is, slower they improve, relatively. PCs not included.

I mastered ton of my spells on very weak mobs and just spamming them as an invoker

And think about how much faster you would have done it, if you did it on powerful mobs instead.

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Can't find the post, but I'm certain one of the imms posted so.

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Invokers do gain a benefit from casting on tougher mobs like everyone else, but unlike every other class, do not suffer a penalty from casting on weaker mobs.

Could just be misremembering things though.

Perhaps my take on "just how hard" spamming spells as an invoker should be is skewed towards easy, but the last time I tried one, albeit only up to the mid 30s, I found that my spells went up very quickly by spamming the on low level (1-10) mobs.

I would assume then that the difference in skill/spells gain rates between fighting a bunch of low level NPCs as a warrior and spamming spells on a level 5 fish is quite different?

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