Oh, hey, I did hit 1000.
Neat! Thank you.
Oh, no, I didn't mean Brutal Fairy shouldn't be a thing. Lemme explain a little better:
Demons, inherently, have a modifier they pass on when fused. For example, Huo Shu pass on Fiery. A perfectly normal Huo Shu, if Fused with a Goblin, makes a Fiery Goblin.
However, the Tower sometimes randomly applies modifiers to demons... however, it does so according to some rules that basically are designed to prevent badly mismatched modifiers. These rules forbid Brutal Faeries, whose Strength and Vitality are deemed to low to actually be a good fit for Brutal.
Enemy summoners have an AI for creating their parties: on the topic of modifiers, they also follow this rule, so a Brutal Faerie is not possible from them either. Corpse encounters also use this rule.
HOWEVER: When a demon does have a modifier, it overrides the one it naturally passes. To resume our Huo Shu example, if a Huo Shu managed to spawn with the Brutal modifier (which it does qualify for), it would now pass Brtual, rather than Fiery, if Fused.
When I said a Brutal Faerie would be hard to do, I was referring to two facts: 1) There aren't many demons that naturally pass Brutal, 2) Faeries in the wild can't qualify. So it IS possible... but it requires something like our Brutal Huo Shu to appear, or someone being patient enough to wait for a Chachapuma or other demon that naturally passes Brutal when Fused.
As to Lifegiver Slimes... it actually isn't the worst idea ever. They do end up with monstrously good Vitality and HP, and their Magic gets bumped just high enough to be passable. There are probably worse things to have than a ridiculously tanky healer, even if it does have iffy Magic and a slightly less than average Speed.
Notably: Lifegiver Slime *is* allowed by the various random systems... Slimes have just barely enough Magic to qualify. It is in fact, one of the few modifiers Slimes *do* qualify for.. their horrid Agility actually shuts them out of a great many.