Some things I noticed, might help with reducing hacks.

Hero Mode rooms are often swarmed with obvious hackers, which is where I saw a couple things that could help the game detect if a person is hacking:

When a one hit kill hacker shoots a Mutant after time runs out and the round ends, they're shots will not be an instant kill. In fact, it will do the normal amount of damage. In other words, once the round ends, their one hit kill hacks don't work. If there's something already in the games programming that can stop this hack, it shouldn't be hard to change the code for any game type's startup to include it.

Second, one hit kill hackers often don't get MVP, even if they have hundreds of kills. Example:

Basically this just means that the game registers the kills by the hackers, but it doesn't register any additional damage done by them. I'm not a programming expert, but a few lines of coding should be able to see any major abnormalities without putting too much strain on the game engine. Something along these lines could probably detect hackers in Hero/Mutation mode, as long as the data it checks is stored server-side, which I'm pretty sure is the case:

On the death of a mutant, check how much total damage has been logged for shooting the mutant, and how much damage he did to himself with his 'g' ability. I'm not sure if the number of times a mutant used his ability is logged, but if it isn't, it would be easy enough to give each player a variable starting at 0 and adding 1 to it whenever their special ability successfully activates. If the total damage he received was less than, say, 1500, the person who got credit for the kill would be disconnected.

A number around 1500 would be a good since it would still detect a hack if a mutant took well over thousand damage from other sources before the hacker's kill-shot, but wouldn't falsely kick someone unless a mutant took an extreme amount (as in over 1500 or more, which is basically not possible) of unregistered fall damage.

I don't know what coding language is used by Cross Fire, but implementing this shouldn't be too much more complicated than adding something similar to "If dmg_pl1 + dmg_pl2 + ... + dmg_pl16 + (ablty_count*500) < 1250, disconnect the player who received the kill" to the programming linked to a mutant's death. Also, while something like this might work in other modes besides Hero/Mutation, there would be a much higher chance of false kicking because of the lower HP, and it would put a lot more strain on the servers due to the high number of kills per game.
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