- While you can return colorless cards to your hand with this ARTS, because Colorless is not a color, you may not select Colorless as a color for Rainbow Art's secondary ability.
- This happens even if the card has Multi Ener because Multi Ener only pertains to payment of cost.
- You cannot select the same color twice, and therefore cannot activate the color's ability twice.
- You can still activate this ARTS's secondary ability if you are unable to return either a spell or SIGNI. In this case, you can only select 1 color.