"Ultimate Crystal Magic" Rating Score by 福人ズッコケ

By sending 7 types of Crystal Beasts from his hand, deck, and field to his GY, a trap card that can special summon the ultimate jewel god Fusion Monster as a fusion summon.
The Ultimate Gem God Fusion Monster currently only exists as a Rainbow Over Dragon, so it is effectively a fusion method exclusively for it. It's not likely that there will be more in the future.
Being able to procure fusion materials from the Deck is powerful, but it is weak against removal because it can only be activated when his own Crystal Beast is destroyed in battle. Also, since 7 types of Crystal Beasts are required, all Crystal Beasts must be adopted for this card during the construction stage, and if even one is missing, it will rot at that point.
If the Ultimate Jewel God leaves the field due to the opponent's effect, it also has the effect of reviving the jewel from GY. Ultimate Jewel God is 4000 on its own and is extremely strong in battle, so there will be many cases where it will be removed by its effect. If he used the effect of (1), he should have enough Crystal Beast in GY. A card that is strong as long as it can be activated, but also has various peculiarities.