I know this is a lot to read and take in but please, if you really want to know what's going when those shots aren't hitting or those melees make the sound but nothing happens, take the 7 minutes and read my analogy. 1. Your download/upload speed and ping you see from any testing is irrelevant since it is coming from a server and not the host of your game. 2. Your connection to the host will vary greatly in comparison to others in every ganr. 3. Your download and upload speed is also irrelevant if it is at least 3 mbps as online gaming truly does not require much more. 4. Your ping time is most important if the speed requirement is met. Think of speed vs ping in car traffic terms like this: the connection from you to your host is like a road between you and your destination. Every person going to the same destination as you is going to have a different road. The speed limit on the road can be compared to your ping. So if your have low ping, say 40 ms or below, the speed limit on your road is pretty high, we'll say it's 100mph to stay simple. Now, your download/upload speed is your car's capacity for people. Now the requirement to move the car is obviously one person. More people in the car do not make it travel down the road any faster. Now, on this roadway, all cars on the same road travel at the max speed. So if you had say a 40ms ping connection to your host and have let's say 100mbps download, this basically means you are driving a mini van 100 mph to your destination. On the same road is another person but the difference is, they have a 5 mbps connection. Remember, all cars travel at the max speed limit of 100 so your 5 mbps, 40 ms ping connection is the equivalent of you driving a motorcycle on the same road as the mini van. Are you going to reach the destination faster than the mini van? No. You will simply just arrive there with less empty seats which is irrelevant since only one seat is required to be filled. Now let's think about say a 180ms ping, connection with the same download upload speeds as above. The higher ping means a much lower speed limit. Instead of traveling 100 mph you are now going 25 mph. The people on the other road are going to arrive at your host, your destination, faster than you. THIS is what creates lag. The lags cause can be honestly anything from a bad WiFi signal in your house, equivalent to say a bad transmission on your vehicle, to a bad gateway router somewhere between you and your host, the same as say hitting many detours while trying to get there. I hope this clears some confusion on why lag is such an issue and so random with peer to peer games.