"Book of Moon" Rating Score by ブルーバード

At the beginning of its introduction, it was not very strong as a general-purpose card because it only bought time and tended to lose money. At the time, due to priority, it was powerless against activation effects, and Monarch and his Gadget had many effects when summoned, so it wasn't very reliable as a hindrance. At the time, it was said to be weaker than the Ennecon as an obstacle. Nonetheless, it was noted for its ability to reuse reverse effects, and was recognized for its high ability as a combo card. Since Sacred Magician was alive in the Zeroyon environment, this card was often used in Mutant Chaos, such as collecting a lot of his spells and aiming for mass removal in combos with Sausaku. For that reason, it was designated as a restriction even before it emerged as an obstruction card, and it had strength.
The turning point was the appearance of Synchro Summoning. By turning Synchro material monsters into face-down defense, the flow of interfering with the opponent's Synchro and making the opponent's monster stand still was highly evaluated, and it was useful as a new general-purpose card along with "Compulsory Evacuation Device" and "Black Horn of Heaven". After that, it was designated as a restricted card for a long time due to the revision of the activation effect rules and the Xyz Summon.
In modern times, it is not regulated because its power is not extremely high, but its strength is still one step ahead as a general-purpose card. It is flexible enough to act as a hindrance in any situation. If you can combo with your own deck and feel that it works well, put it in for the time being.