If a spell has X in its mana cost, you must choose 0 as the value of X if you cast it without paying its mana cost
It wasnt very good in an environment where creatures were hardly played and even if they were, your opponents would probably just take the cards anyway
Whenever a creature or planeswalker an opponent controls is dealt excess damage, if a Giant, Wizard, or spell you controlled dealt damage to it this turn, draw a card
So much so this sees plenty of play in decks with no discard synergy
This deck has to be split between a traditionally sacrifice-centered strategy and a strong amount of removal
So, although this isn't a "banned" card, it started an almost 20-year ban on new Kadabra cards, crazy