Trade Secrets First Printed: 1998-OCT Banned: 2013-APR Trade Secrets is a flag-bearer for the banning principle of Cards which interact poorly with the multiplayer nature of the format, as its a cheap spell that allows two players to collude
If you don't reveal an Equipment card, or if the exchange can't be completed (such as if Arcanum Things is no longer on the battlefield, you don't own Arcanum Things, or the new Equipment can't be attached to the creature Arcanum Things is attached to), nothing happens
I tried to ensure none of these would just ruin any of those formats
Convoke doesn't change a spell's mana cost or mana value
Golbez, Crystal Collector's last ability checks at the moment it would trigger to see if you control four or more artifacts
When this iteration of Sisu comes into play, you get to banish all your opponent's characters with two strength or less