Ishihara Test by Liam Levanon
They see 5 cards, front and back. They're all CLEARLY grey. After a "color-blindness test", somehow they can finally see their super bright colors. Everything is examinable!
Magic Rainbow by Juan Tamariz (Hardcover)
The most anticipated book of the last 2 years, Juan Tamariz's magnum opus on magic-performance theory. FINALLY BACK IN PRINT.
Rainbow Road by Kyle Purnell (CARDS INCLUDED)
A 3-phase powerhouse that gets more impossible each phase. The finale blows everyone's minds. The ORDINARY cards all change color. START LEARNING INSTANTLY.