To get the two keys they're on two levels 1. The level sunset vista get three cortex icons and complete the bonus. 2. The level the jaws of darkness get three cortex icons and complete the bonus. NOTE: the first key unlocks one level on the 2nd island up from the level boulder dash. NOTE: the second key unlocks one level on the last island just up from lights out.
We all know about if you beat Cortex you win the game. However, there is another way to finish the game without beating Cortex. Collect all the gems (Or just use the Super Password) And go to the Great Hall. Once you get there, instead of jumping over the one pit and going to the goal at the end of the level, a gem platform will appear.
Go onto it and it will take you to another gem platform, carry this on until you get to a giant wooden platform. You then go to another set of gem platforms and carry this on until you get to a third giant wooden platform with a big red curtain blocking a stone arch. Go up to it and it will go up and reveal the female bandicoot.
There will then be a minimovie where the two bandicoots fly off on top of a giant buzzard and you'll have completed the game!
When at the polar floor, you'll see the little bear,go on it and jump on it 10 times and before you know it he'll give you 11 lives. (you can only do this one time in the game).I hope you'll enjoy the lives,use it wisely
In any level to get a gem break open all the boxes and to get the two keys get a gem on the great gate and upstream and you will find that when you play these levels again that there are gems.
You can step on them at the end to take a different route and on upstream the gems also go behind the log in front of the waterfall.
On castle machinery at the beginning there is a gem elevator ( if you have the gem ) that will take you up where there are tons of lives an right after that there is another elevator going down that leads right to the end.