Sometimes flooders are near impossible to catch. All I can suggest is you slow your scroll speed down (via settings > options > set scroll speed to very slow) and pay attention to the icon the flooder is using, the names they are using i.e if they are using all caps there's a good chance that won't change, if it is all lower case the same thing, if they began flooding with ! and went down the alphabet with a, b, c, d, e, f, g names, etc then pay attention to that as well.
I usually either log onto invisible for a tick (remember that you are on invisible and don't use it for too long!) and run the scroll bar up and down for a few minutes (just hold the left click on your mouse/track pad and drag the scroll bar) in search of a name. Usually a flooders imagination runs out and they return to the same names a few times so be mindful of that as well.
If this is a flooder who is cloning people, it is also a VERY good idea to flag the people you are speaking to in main chat or main characters in the main chat room as these people are usually the biggest targets. Everytime I log onto chat I flag all the people I speak to often and all the people who (as bad as this may seem) have been known to be quite argumentitive in the past as they are also prone to such.
If someone who is just sitting in the room is the person who is being cloned, flag them and stick to their name for a while to see if the cloner comes back.
How do I spot a cloner? Usually a cloner will flood/type consecutive messages that are inserted into the room way too quickly which are obviously copied and then pasted; You can also spot a cloner when you are conversing with a user and there is a message posted too quickly before or after the user has typed another, separate thing. Also, just trust your instinct. See a suspicious name? Screenshot their IP and keep it in an unsaved paint document. This can really come in handy in these instances.
Again, trust yourself, don't just assume you'll be wrong because 9/10 times you've seen this all before and your judgment is spot on.
