Moving Target

If you are trying to make a ranged attack against a moving target, you get a +2 modifier to your difficulty.
This doesn't apply if both you and your target are moving at the same speed, in the same direction. In these cases, the relative velocity is zero.
This doesn't apply to targets that are moving standing in the same place (melee combat, dancing, doing pushups, etc.), unless you are making a Precision Strike. The GM decides when a target can be considered to be moving.