Dude I can see the weakness in every character, just because I see it doesn't mean it's non-metagamingly exploitable. 

Sometimes in character logic only goes so far, I'm not talkin' about yer mech Green, your mech has a hilariously blatant weakness. 

But I'm getting at stuff like: Golden Age Green Lantern's weakness was wood. 

Wood!

How would you be able to learn this information in combat? Nobody in the arena has wooden weapons. Would they just conveniently be disarmed and find a stick to beat the shit out of him with? 

Sometimes weaknesses can be ridiculously dangerous, other times super obvious. But just because it's obvious doesn't mean it's exploitable. Example: Superman. 

Kryptonite, a material that's dangerously radioactive to humans. It's also incredibly rare. 

And then you've got normal human characters who are low tier, who are all weak to bullets. But we all know what happens when you shoot bullets in an RP. 

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