These cards are worded specifically to bend the rules of Magic, letting you play as many of them in your deck, with a bonus or two for having more of them in play or having played them during a game
Two copies of "Nordic Relic Megingjord" can double the attack of one of your "Nordic" or "Aesir" monsters, which also causes them to be unable to attack directly, but also gives cards like "Guldfaxe of the Nordic Beasts" 3200 ATK to beat over monsters that would be normally out of its reach, while "Aesir" boss monsters can try to pull a "Utopia Double" move and hit stuff for 8000 ATK (in case of "Odin, Father of the Aesir")
Looking back on the previous two lists, Im pretty satisfied overall with my predictions, but lets see if we can improve upon them as we move into Aether Revolt
The crease already put it at a 7 and since that alone bumps it down so much, it comes with some leniency on the whitening
Their boss monsters, Prediction Princess Tarotrei and Prediction Princess Tarotreith , has an effect that allows the player to reliably flip monsters face-down or face-up, allowing you to use their effects again