The following are heroes that, while still generally fighting on the good side, are more than willing to kill another being, in order for this to be considered different from cold-blooded murder, the individual said hero kills is almost always corrupt or criminal in some fashion or they kill in self-defence.
These heroes are still very strict in terms of not killing innocent people and can be considered in some ways like soldiers or Evil Exterminators. They will not hesitate to end the life of a wicked or crazed opponent if they feel it will save the lives of themselves or innocent people.
NOTE: Characters that kill in cold-blood, with no concern about "innocence" are murderers and serial killers, even if misguided. Lethal Heroes always have strict codes concerning who/why they kill and VERY few Lethal Heroes enjoy killing, indeed they often hate the act but do so out of duty or survival.