to explain it simply:
i was playing checkered deck (only has spades and hearts)
i got that tarot card that turns 3 cards into diamonds
the tarot card's description had colored "diamonds" as red, the color used for the hearts suit, instead of its usual color that it has with every other deck (orange, to match the color of the diamonds suit)
so, I thought that it'd turn the cards into hearts and not diamonds (since that's what checkered deck does)
however, when using the tarot card, it just turned the cards to diamonds
i don't know exactly what platforms this bug is on but i experienced it on pc