I've always felt that darkness is also a force, so if the righteous heroes have dark forces superimposed on them, they're more powerful, like the evil Justice League in the movie. Wonder Woman is charming, Batman is gloomy, and Superman has a power that sweeps everything away.
And in the real world, Luther and the Joker, who had killed all over the world, became very unbearable in front of them. The clown lacks the breath of death and madness, and has no skills that can be used by him, just like a dispensable ant. The threat to the Evil Justice League is minimal.
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