Supers in otherwise-realistic settings

[Varyon]

One Supers setting I came up with, inspired largely by a combination of Worm and Dr Horrible's Sing-Along Blog (and probably the way I had a mechanic from a game system focusing on Supers, the name of which escapes me, described to me), had an interesting quirk in the way superpowers functioned. In general, supers and their henchmen are markedly more durable than expected (in GURPS terms, IT:DR, Regeneration, Hard to Kill, and a touch of Serendipity), but those they harm - even indirectly, with collapsing buildings and the like - benefit from the same improved durability, keeping death tolls rather low. Supers can bypass this effect, by a mechanism called Killing Intent. Doing so is rare, for a variety of reasons. First off, a murderous super is likely to have others (even fellow villains) come down on him hard, either killing him directly or, more likely, capturing him and delivering him to the authorities, where execution is likely. Next, Killing Intent reduces one's own durability - to that of a normal human if enhanced durability isn't part of the character's powerset - which is obviously dangerous. Finally, supers who actually use Killing Intent successfully risk losing their minds; there would likely be a few high-priority supervillains who were relatively normal supers before killing somebody made their minds crack. I'll note here that using Killing Intent against supers who aren't responding in kind isn't quite as dangerous - while it does shut down their defenses, the fact they are holding back means you get some degree of benefit from the less-lethal nature of their own attacks. Due to this, some supers will actually use Killing Intent against other supers without any actual intentions of killing the target, simply to effectively increase their own firepower; this is dangerous, as it means a mundane person with a gun can end you readily, or your opponent might opt to use Killing Intent of their own (or you might accidentally actually kill them, with the negative repercussions of doing so). Similarly, you don't have to use Killing Intent to actually cause someone to die - they are more durable, but hardly immortal. Also, an effect that is sufficiently divorced from human action can sometimes bypass the protection (*cough*convoluted deathtraps*cough).

The way I'm thinking it would work, this protection would have a few tiers to it. The strongest, Tier 4, would be in play for super vs super combat (basically, one's own enhanced durability stacking with the enhanced durability from being targeted by a super). Tier 3, a bit less effective, would be what supers enjoy against mundanes, and henchmen enjoy against enemy supers. Tier 2, less effective still, would be what mundanes enjoy against supers, and henchmen enjoy against mundanes. Tier 1, the least effective, would be what mundanes enjoy against henchmen. Using Killing Intent makes a super function as though he or she were mundane, but lowers the level of protection the target enjoys by 2 steps. Most indirect effects (like collapsing buildings) lower the level of protection by 1 step, but it is possible to lower it further with more complicated arrangements (as in the case of the deathtrap clause, above).

Essentially, this would be having a lot of supers tropes be in play as a direct result of the way the powers work, and with people being aware of it. The setting was going to have supers start showing up after superhero comics were fairly well-established, meaning there would be a strong inclination for those who gained powers to go out as costumes. Taking a cue from Worm, there would also be a massive threat (akin to Worm's Endbringers) justifying tolerance for costumed maniacs running around.