Originally Posted by Fat Furai
CB Lucario is simply outclassed by Terrakion, and Skill Swap Deoxys-S has been argued above and was proven to be too situational, making it very often useless.
CB Lucario being outclassed by Terrakion is highly subjective. While Terrakion has higher Attack and Speed, Lucario has a way to hit Giratina hard with Crunch, priority in two forms, and a much better typing. The two preform similar roles, but being outclassed is a whole different matter; CB Terrakion vs CB Lucario is a matter of preference, not inferiority. I've used it in the past many times, and it has never been an inferior Terrakion.
I think I made this point in my earlier post, but whatever.