This game had some crazy completion requirements, with you having to find and collect all 50 monkeys throughout the game in order to get the true ending. I could never do it as a kid as I, one, didn't have the attention span, and, two, some of said monkeys were extremely well hidden and a pain to obtain. This game was also developed by Toys For Bob, the same studio that would go on to develop Crash Bandicoot 4, a game infamous for its collectables and how much of a nightmare it is to fully complete.
Is Madagascar 2: Escape 2 Africa... a prototype for Crash Bandicoot 4?