Well I yust ralice that if the opponent pass and you use a card that alow you to use another one without giving the turn to the oponent and then you pass the turn dont end and if the opponent pass there you start first. can be abused
Yes, the tricky part is that the card language varies: SOME cards use the "Cantrip" keyword, while SOME explain it in full sentences (without the word "Cantrip").