Removing Mana from the game...

[Insomnia]

I think the bigger the mob, the more mana you should be able to drain from it. Maybe it makes sense to count in not only the mob's class, but also other attributes, such as damage, total exp, procs, ethereality, aggressiveness, alignment, etc... actually, we have a good example of such calculation – Spirit of Conquest does a very good job calculating how many points each mob is worth. Some similar formula could be used for energy drain (but casters should give more than non-casters, of course).

Speaking of numbers:
* 62 mana from the kobold sage is not something anyone would bother draining, but seems just about right for the mob of its size
* 1000+ mana from wardens in Herbalist II – this, I think, is a perfect ratio of value vs. risk, especially given that they are in a funky magic room
* Some other mobs that feel right for me are Shemiz, Stakur and Alocer in Darken Wood.
* Being able to drain 2000 mana from venerable plantwraith is definitely disbalanced. They should give maybe 5 times less.
* An ogre magi should be worth not 108 mana, but 1080 mana... but if you tell me it's more "ogre" and less "magi", I'll accept it.

[Gorka]

From a programming perspective... I doubt mobs have an flag to denote if it's a caster or not. They probably just have a well of mana. Maybe they can tell it's a caster by the size of it's spell list? But your idea suggests the mana well should be proportional to the attributes of the mob. So unless the game starts overriding mob mana with a calculated mana... all the spell casting mobs would require editing in that case. Not an attractive option to edit all sloth mobs I would think.

The fact is, most mob don't cast spells, or have much mana...

A proper solution would be to give back mana in other ways, regen, vaults, improved spectral, weapon drains etc... and fix the actually really small number of offending mobs... I doubt that's what will happen though. There seems to be a pattern of "legalizing exploits" rather than fixing them and giving back in proper ways. The irony is, It wouldn't surprise me if the first solution, is even more exploitable than what we have. Will wait and see I guess.

[Hung]

I left the game in 2017 and logged in yesterday just to see the new stuff.
And I tend to agree with Gorka: things became way worse. The energy drain - which allows to instanly gather 2-3k mana - changed everything.
Sloth was an RPG when I left. And now it became sort of an action game.

p.s. Never had a problem with 5-10 mins of group regen breaks.