Board games are diverse, so consider the number of players, age range, and playtime
In much the same way that I embraced the strange and unusual when constructing my Shattergang Brothers Eldrazi deck, Yennett gave the super gimmick weird decks a general to champion, all wrapped up in a fun sphinx
Festering Newt Ok, so you want me to pay 4 mana for a 1/3 creature, then next turn pay 2 mana to tutor out a Bubbling Cauldron, then wait another turn to tutor out a Festering Newt, then pay another mana and activate the Cauldron sacrificing Newt in order to kill a creature and drain 4 life from my opponent
Chevalier de Fleur X WIND Level 8 [ WarriorSynchroEffect ] ATK 2700 DEF 2300 "Fleur Synchron" + 1+ non-Tuner monsters Once per turn, during your turn, when your opponent activates a Spell/Trap Card (Quick Effect): You can negate the activation, and if you do, destroy that card
TL;DR: If someone tries to draw extra cards, they either end up discarding and drawing, or milling instead, so they never actually go up on cards
It should be noted that it is difficult to handle compared to a general trump card that can ravage the field by itself