Yu-Gi-Oh: 10 Most Powerful Unbanned Cards In The Game
7. True King Of All Calamities
Probably the fairest card on this list, True King Of All Calamities is a rank 8 XYZ monster with 3000 attack and defence. Its ability is one that literally stops your opponent from playing the game for one turn.
By detaching one material you're able to name one attribute, all monsters your opponent controls become the named attribute and all monster effects from monsters with the named attribute are negated and can't be used, they also can't attack or change battle positions.
True King has become easier and easier to summon, once limited to certain decks the introduction of Crystron Halqifibrax has made True King easier to summon for nearly every deck. Going first and making this colossal monster is a breeze and it's not fair that you get to go crazy with your monsters but your opponent can't do anything with theirs.
In general, cards that prohibit or stop your opponent from playing the game have no business being legal.