Don't know if it is right, but to corrupt monsters yourself, I think you need the abillity "Tainted by the Lost", that you get when you drink the seed of the corrupted minotaur, that attacks the golden bastion at the beginning of the game.
Hohoho, what should i explain...
Okay let talk about your topic and follow topic about my test.
It will not prevent. I'm sure it has different dialog but normally it isn't.
You can grow as much as you want. Maybe there is limit behind the scene? Now my topic.
Rescue experiment
It's 50/50 chance, I dont need parasite anyway.
My experiment outcome is no matter what 30 - 70 there's chance to rescue but not 100%.
Over 80 would be major corrupt and it isn't implement yet.