I have 3 cards that I'm not sure the rarity of. They have silver letters with little dots of rainbow color. Also the card is holographic but when you move it there are 2 horizontal lines and 3 vertical lines of rainbow colors and they move sideways whenever you turn it. Thanks that's the best description I can give.Update:
The cards are Zoa, Goblin Fan and Skull Dice. All 3 have same rainbow effects as above. Also just found one card called Covering Fire that is like an Ultimate Rare (shiny name and attribute) but the card has a cooler and more intense shine.