The keys are not that difficult to find in this game but maybe you have trouble to find all of them.
Or maybe you are just to lazy 😉

1-2

1-3

1-4

1-5


2-2

2-3

2-4

2-5
its blocked by a wall but inside there is a bomb moster thing, just wait or spam tail whip


3-2

3-3

3-4
on the jump section with the icecubes jump left instead of right

3-5

at the portal section just fall down with the platform

4-2

4-3

4-4
bevor you dropp down to the platform with the lever, stay on the platform above it

4-5
after the section with the red, green, red blocks stay on ceiling and jump over the gravity switch

Now you have access to the bonus level.
Gongratulation 😀
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