Egg Slam!

From BoardGameGeek:

Egg Slam! is a color-mixing game in which players race to call out the colors of eggs laid by the rainbow birds. The deck consists of cards that birds in red, yellow, or blue with a background color that doesn't match the bird as well as egg cards that feature a rainbow either in the center or on the background. Place three cards face up in separate piles, then split the deck equally among players. Players take turns flipping a card from their deck onto a pile. When an egg card lands on a pile, you need to yell out the color you get when you combine the colors of the birds (or backgrounds) on the other two piles depending upon whether the rainbow is on the egg itself or on the background. Whoever calls out the correct color first wins the egg card, and once the decks are exhausted, whoever has collected the most eggs wins.