Killer Bunnies and the Ultimate Odyssey is a new take on the collectible non-collectible KB line, with Jeffrey Neil Bellinger once again putting the rabbits through the grinder. Players can construct personalized decks with the cards from any deck up to a maximum of sixty cards in each game.

When the insatiable appetite of Killer Bunnies game fans demanded more, Playroom looked to Killer Bunnies creator and game designer Jeffrey Neil Bellinger to coordinate the development of, like other games in the Killer Bunnies family, a non-collectible game that can offer variations through different color nick-named deck options. However, this time a new desire expressed by the huge Killer Bunnies fan-base has been fulfilled: Killer Bunnies now has a constructable game variation. Though still not collectible or random, players can now buy starter decks and booster expansions for Killer Bunnies and the Ultimate Odyssey and then use any combination of those cards to form their own constructed decks to play against opponents. Unlike in Killer Bunnies and the Quest for the Magic Carrot, where up to eight players play with the same deck of cards, all sharing the same draw pile, Killer Bunnies and the Ultimate Odyssey has players each draw only from their own constructed deck of 60 cards.

The setting for the new game is an ultimate race to build a bunny society on planet Earth. Killer Bunnies and the Ultimate Odyssey pits players against each other as they struggle to gain Civilization Points, by building cities and increasing their bunny populations. Players gain points by developing their own civilizations or by using zany weapons and hilarious scenarios to destroy their opponents.