The boardgame Relic is based on Warhammer 40k characters questing through space. In that setting, there are dark bargains you can make with the forces of chaos. It’s a constant temptation, and many characters struggle against it constantly. Those that succumb often become incredibly powerful, but lose themselves to the monstrous forces.
Relic pays homage to this setting detail by creating Corruption cards. Most are bad to draw. While playing, you’ll occasionally get the option to draw corruption cards for various benefits (more money, more power, etc). If you ever acquire 6 corruption, you lose. There are also effects that can force you to draw more corruption cards against your will, so the more you have already the more risky you’re playing with your soul. All good so far.
Here’s where it goes wrong. There are some characters, the sThpace equivalents of paladins and clerics, that are naturally resistant to corruption. It’s hard to corrupt these guys in the lore. To address this, the game gives these characters various ways to minimize the costs of drawing corruption cards. If most characters lose when they have 6 corruption cards, a paladin-style character might lose at 8 corruption cards. Another similar character might be immune to the negative effects of the cards, but still lose when they have 6.
But how does this feel? It makes the players running these characters fear corruption less, not more. Every time I see these space-paladins saying, “Sure, I’ll draw some corruption cards. I don’t need to worry about the bad effects as much, why wouldn’t I?” No one has more corruption than the paladins.
The design should work the opposite way. Evil characters should be given incentives to draw corruption cards, while good characters should suffer additional penalties. This would make the players feel the concept.
I’ve been messing around with a homebrew RPG system with a similar system. Players will be able to risk being corrupted by dark forces regularly in exchange for mechanical benefits. One of the core features of following the Path of Light (an umbrella option for divine power source characters) is added vulnerability to corruption. If you enter a dark bargain as a divine character, or use dark magic, you’re more likely to suffer corruption than anyone else. This means you, the player, fears it more… As your character would.