Odyssey Prime was a noble experiment. Take all the d20 worlds you can grab (or buy) and link them all together with a Stargate like device to transversing the multiverse. And for good measure include the in-house rules of Unisystem.
The game was a great idea, but something about it never caught on with everyone. Regardless the ideas are sound and this is a good adventure based on the simple idea that everything is better with velociraptors.
Worth it for the dino-stats alone really.