This porn game had an interesting (but maybe questionable) game mechanic of having you send goblins to attack heroines, with the knowledge you would fail a million times. Even though you fail, you gain EXP, so you grind up the EXP to level your units enough that you eventually overwhelm the "hero". Obviously grindy, but interesting. The animation isn't bad either, if you are down with goblin males fucking human women.
https://store.steampowered.com/app/3823290/Heroine_Conquest