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?

You are Dead, Dead Dead
You are Dead, Dead Dead
Thought you were hot, guess what you're not
You are Dead, Dead Dead
Brought your whole adventure to a screeching hault
You are Dead, Dead Dead
Your heart has stopped and your brain is cold, you are so so dead
And now your body is starting to mold, you are so so dead
This Dimension, cuts like a knife
You are Dead, Dead Dead
What a pitiful waste of a human life
You are Dead, Dead Dead
Your heart has stopped and your brain is cold, you are so so dead
And now your body is starting to mold, you are so so dead
Aww, such a sad sad story
You're gone empty head in the red, Game Over
You're Through, Gone
How does it feel to be dead? (You are dead~)
Bye Bye, You're history, You're Through! You're Dust
I hope you improve your lousy score
Adios, See you later, Bye Bye
Try Again!
You are Dead, Dead Dead.

An almost perfect finale to the original Halo trilogy.
Compared to the jump from Combat Evolved to Halo 2, the jump from Halo 2 to 3 isn't nearly as drastic and I missed the added variety from Halo 2, playing as the Arbiter for half of the game, however this does also help add to the game's story, controlling Master Chief for the entirety of the duration.
Duel wielding has sadly been toned down slightly from Halo 2, which was my favorite thing to mess around with in the previous game, however it's still present and the gunplay feels smoother than in the previous games.
While the enemy and weapon balancing in Halo 3 feels much more refined compared to Halo 2, some mechanics such as the checkpoint system have still not been fixed, even if they aren't as frustrating as they were before.
The soundtrack is wonderful, one of the best to come from the series, with Halo 2 Anniversary's OST only coming close.
The levels, while long all feel varied and interesting and while I don't feel there's nearly as much variety as in the previous title, Bungie clearly went for quality over quantity and it shows.
Overall, Halo 3 is a wonderful little bow to wrap up their original trilogy of Xbox shooters, it's aged gracefully and has arguably the best multiplayer in the series to boot.