playstation one demos

i am looking for a game i dont know what it was called but i do know that it was on one of thefirstPS1 demos

i also know that the demo had a T-REX and a mannaray that you could controle. i think it also had rascal and abes oddworld

the game that im after on that demo, at the end it tested your IQ. you stood on a platform and bricks would roll toward you and you had to get rid of all the black ones

so please if you have any idear what im talking about it would be very helpfull