Alright. I had been gone a while and came back and had perplex used on me in a friendly game. But it was a use that really generally isn't used and I knew USED to be an illegal action. But looking at the wording I couldn't figure out why it would be illegal now.

Basicly they were perplexing their defence up so when I would attack them on my turn I'd deal with an upped defence. I knew this used to not be a legal action. When did it change/if it did?

it was always a legal action.

however, prior to The Fantastic Four starter, perplex lasted until the end of your turn. so raising your defense was foolish because it would just go away before you were ever attacked.

once perplex was changed to last until the beginning of your next turn it made perplexing up your defense or perplexing down your opponent's attack or damage actually useful

Ah Ok. That explains why I didn't know about it. Thanks!